A diver rowing at the rate of 5 km/h in still water takes double the time in going 40 km upstream as in going 40 km downstream. Find the speed of the stream. -Maths 10th

A diver rowing at the rate of 5 km/h in still water takes double the time in going 40 km upstream as in going 40 km downstream. Find the speed of the stream. -Maths 10th
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1 Answer

Answer :

5/3 km/h Step-by-step explanation: Speed in still water = 5km/h Define x: Let the speed of the steam be x Upstream speed = (5 - x) km/h Downstream speed = (5 + x) km/h Time taken going upstream: Time taken = Distance ÷ Speed Time taken = 40/(5 - x) h Time taken going downstream: Time taken = Distance ÷ Speed Time taken = 40/(5 + x) h Solve x: The time taken upstream is double the time taken downstream 40/(5 - x) = 2 (40/(5 + x)) 40/(5 - x) = 80/(5 + x ) 40(5 + x) = 80( 5 - x) 200 + 40x = 400 - 80x 120x = 200 x = 200 ÷ 120 = 5/3 The speed of the stream is 5/3 km/h
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Related questions

A motor boat whose speed is 18 km/h in still water takes 1 hour more to go 24 km upstream than to return downstream to the same spot. Find the speed of the stream. -Maths 10th

Description : A motor boat whose speed is 18 km/h in still water takes 1 hour more to go 24 km upstream than to return downstream to the same spot. Find the speed of the stream. -Maths 10th

Last Answer : The given speed of the motor boat in the still water is equal to 18 km/ hr. The given distance travelled by motor boat is equal to 24 km. The time taken to travel 24 km downstream by motor boat = 1 hour. x=122=6 km/ hr.

A this usual rowing rate, Mohit can travel 12 miles downstream in a certain river in 6 hours less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 24 miles round trip, the downstream 12 miles would then take only one hour less than the upstream 12 miles. What is the speed of the current in miles per hour? A.2.5m/hr B.4 m/hr C.8/3 m/hr D. 5/3m/hr

Description : A this usual rowing rate, Mohit can travel 12 miles downstream in a certain river in 6 hours less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 24 miles round trip, ... current in miles per hour? A.2.5m/hr B.4 m/hr C.8/3 m/hr D. 5/3m/hr

Last Answer : Answer-C Basic Formula: Speed of the stream = ½ (a-b) km/hr Explanation: Let the speed in still water be x m/hr Speed of stream be y m/hr Then, speed upstream = x-y m/hr and Speed downstream = x+y m/hr 12/x-y - ... 1] 3y^2 = 8 y so, y = 8/3 speed of the current = 8/3 m/hr = 2 (2/3) m/hr

Thanu can travel 24 miles downstream in a certain river in 12hrs less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 48 mile round trip, the downstream 24 miles would then take only 2hr less than the upstream 24miles. What is the speed of the current in miles per hour? A) 2 / 3 miles/hr B) 8 / 3 miles/hr C) 7 / 5 miles/hr D) 3 / 5 miles/hr

Description : Thanu can travel 24 miles downstream in a certain river in 12hrs less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 48 mile round trip, the downstream 24 miles would ... 3 miles/hr B) 8 / 3 miles/hr C) 7 / 5 miles/hr D) 3 / 5 miles/hr 

Last Answer : ANSWER : B 

A boat takes 4hours for traveling downstream from point P to point Q and coming back to point P upstream. If the velocity of the stream is 2km ph and the speed of the boat in still water is 4kmph, what is the distance between P and Q? A.9 km B.7 km C.5 km D.6km

Description : A boat takes 4hours for traveling downstream from point P to point Q and coming back to point P upstream. If the velocity of the stream is 2km ph and the speed of the boat in still water is 4kmph, what is the distance between P and Q? A.9 km B.7 km C.5 km D.6km

Last Answer : Answer- D Basic Formula: Speed of stream = ½ (a-b) km/hr Speed of still water = ½ (a+b) km/hr Explanation: Time taken by boat to travel upstream and downstream = 4 hours Velocity of the stream, ½ (a-b) = 2km/hr a ... + x / 6 = 4 3x + x / 6 = 4 4x = 24 so,x = 6 distance between P and Q = 6km

A man can row 15 km/hr in still water. It takes him twice as long to row upstream as to row downstream. Find the rate of stream? a) 5 km/hr b) 10 km/hr c) 7.5 km/hr d) 6 km/hr e) 8 km/hr

Description : A man can row 15 km/hr in still water. It takes him twice as long to row upstream as to row downstream. Find the rate of stream? a) 5 km/hr b) 10 km/hr c) 7.5 km/hr d) 6 km/hr e) 8 km/hr

Last Answer : Let the man’s upstream speed be x km/hour and downstream speed will be 2x km/hour Speed in still water = 1/2 (2x + x) = 3x/2 km/hour 3x/2 = 15 X = 10 Hence, his downstream speed = 20km/hour Rate of stream = 1/2 (20-10) = 5km/hour Answer: a)

A boat running downstream covers a distance of 20 km in 5 hours while for covering the same distance upstream, it takes 10 hours. What is the speed of the stream? a) 2km/hr b) 4km/hr c) 1km/hr d) 1.5 km/hr e) None of these

Description : A boat running downstream covers a distance of 20 km in 5 hours while for covering the same distance upstream, it takes 10 hours. What is the speed of the stream? a) 2km/hr b) 4km/hr c) 1km/hr d) 1.5 km/hr e) None of these

Last Answer : c Rate of downstream=(20 / 5 ) kmph= 4kmph Rate of upstream =( 20/10) kmph= 2kmph Therefore Speed of the stream= (1/2)(4 - 2) kmph= 1 kmph

A boat is rowed downstream at 15.5 km/h and upstream at 8.5 km/h. The speed of the stream is: (a) 3.5 km/h (b) 5.75 km/h (c) 6.5 km/h (d) 7 km/h

Description : A boat is rowed downstream at 15.5 km/h and upstream at 8.5 km/h. The speed of the stream is: (a) 3.5 km/h (b) 5.75 km/h (c) 6.5 km/h (d) 7 km/h

Last Answer : (a) 3.5 km/h

Ashok can row upstream at 8kmph and downstream at 12kmph.What is the speed of the stream ? A.6km/hr B.3km/h C.2 km/hr D.4km/hr

Description : Ashok can row upstream at 8kmph and downstream at 12kmph.What is the speed of the stream ? A.6km/hr B.3km/h C.2 km/hr D.4km/hr

Last Answer : Answer -C Basic Formula: If the speed downstream is a kmph and the speed upstream is b kmph then Speed of the stream = ½ (a-b) kmph Explanation: Speed downstream a = 12kmph Speed upstream b = 8 kmph Speed of the stream = ½ (a-b) = ½ (12-8) = 4/2 = 2 kmph speed of the stream = 2kmph

A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Description : A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Last Answer : (a) 3km/hr

A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Description : A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Then what is the speed of the stream? (a) 3km/hr (b) 5km/hr (c) 6km/hr (d) 7km/hr

Last Answer : (a) 3km/hr

A boatman can take the same time to row6.5km downstream and 3.5km upstream. His speed in still water 2.5 km/hr. The speed of the stream is. A) 0.75 km/hr B) 2.5 km/hr C) 1.5km/hr D) 7.5km/hr

Description : A boatman can take the same time to row6.5km downstream and 3.5km upstream. His speed in still water 2.5 km/hr. The speed of the stream is. A) 0.75 km/hr B) 2.5 km/hr C) 1.5km/hr D) 7.5km/hr

Last Answer : ANSWER: A Explanation: Given that the speed in still water = 2.5 km/hr Let the speed of the stream be x; km/hr speed in upstream = (2.5 - x)km/hr Then time taken to cover 6.5 km downstream = 6.5 / (2.5+x) ... 5x = 8.75 + 3.5x 10 x = 7.5 x = 0.75 km/hr The speed of the stream is 0.75 km/hr

A man takes 10 hours to cover a distance while traveling upstream on a boat, whereas while traveling downstream it takes 6 hours. If the speed of the boat in still water is 6 kmph, what is the speed of the stream? 1 : 2.5 kmph 2 : 2.2 kmph 3 : 2 kmph 4 : 1.5 kmph 5 : None of these

Description : A man takes 10 hours to cover a distance while traveling upstream on a boat, whereas while traveling downstream it takes 6 hours. If the speed of the boat in still water is 6 kmph, what is the speed of the stream? 1 : 2.5 kmph 2 : 2.2 kmph 3 : 2 kmph 4 : 1.5 kmph 5 : None of these

Last Answer : 4 : 1.5 kmph

A boat takes 27 hrs to travel a distance upstream and takes 9hrs to travel the same distance downstream. If the speed of the boat in still water is 12km/hr, then what is the velocity of the stream? A) 8km/hr B) 6km/hr C) 4km/hr D) None of these

Description : A boat takes 27 hrs to travel a distance upstream and takes 9hrs to travel the same distance downstream. If the speed of the boat in still water is 12km/hr, then what is the velocity of the stream? A) 8km/hr B) 6km/hr C) 4km/hr D) None of these

Last Answer : ANSWER : B  Explanation: Let the velocity of the stream be ‘ y’ km/hr Then the speed of the downstream = (12 + y)km/hr The speed of the upstream = (12 – y)km/hr 9 (12 + y) = 27 (12 – y) 108 + 9y = 324 – 27y 27y + 9y = 324 - 108 36y = 216 y = 6 km/hr

A boat takes 24 hours to cover 128 km downstream and 16 hours to cover 64 km upstream. Then the speed of the boat in still water is: A) 14/3 B) 8/7 C) 3/2 D) 9/5

Description : A boat takes 24 hours to cover 128 km downstream and 16 hours to cover 64 km upstream. Then the speed of the boat in still water is: A) 14/3 B) 8/7 C) 3/2 D) 9/5

Last Answer : Answer: A Explanation: Distance covered in downstream = 128km Time taken in downstream = 24 hours. Rate of downstream = distance / time = a = 128 km /24 hours = 16/3km/hr Distance covered in upstream = 64km Time taken in upstream ... / 2 = (1/2)(16/3+4) km/hr = (1/2)(28/3)km/hr = 14/3km/hr.

A boat covers 14 kms in upstream and 20 kms downstream in 7 hours. Also it covers 22 kms upstream and 34 kms downstream in 10 hours. Find the speed of the boat in still water and of that the stream. -Maths 9th

Description : A boat covers 14 kms in upstream and 20 kms downstream in 7 hours. Also it covers 22 kms upstream and 34 kms downstream in 10 hours. Find the speed of the boat in still water and of that the stream. -Maths 9th

Last Answer : Given, The boat covers 14 km upstream and 20km downstream . at time 7 hours also cover 22km ups. and 34km dwn in10 hours total speed = total distance/total time :.total distance = 14+20+22+34=90km and total time=7+10= ... =90/17 => 5.294km/h => 5.294km/h the speed of boat in still water is 5.29 km/h

A train, travelling at a uniform speed for 360 km, would have taken 48 minutes less to travel the same distance if its speed were 5 km/hr more. Find the original speed of the train. -Maths 10th

Description : A train, travelling at a uniform speed for 360 km, would have taken 48 minutes less to travel the same distance if its speed were 5 km/hr more. Find the original speed of the train. -Maths 10th

Last Answer : Let the speed of train be x km/hr Distance to be travelled = 360km We know that, Time take by the train intially = If the speed was increased by 5km/hr Time taken by train = Difference in the time taken is 48 minutes, x2+5x -2250 = 0 (x+50)(x-45) Speed = 45 km/hr as speed cannot be negative

A boys rows to a certain place and comes back, but by mistake he covers 2/3rd more distance while coming back. The total time for this journey is 20 hours. The ratio of speed of boat to that of stream is 2 : 1. If the difference between upstream and downstream speed is 24km/hr, then how much time will the man take to reach to starting point from his present position? A) 2hr 13mints B)1hr 30 mins C) 2hr 30mins D)1hr 40 mins

Description : A boys rows to a certain place and comes back, but by mistake he covers 2/3rd more distance while coming back. The total time for this journey is 20 hours. The ratio of speed of boat to that of ... starting point from his present position? A) 2hr 13mints B)1hr 30 mins C) 2hr 30mins D)1hr 40 mins

Last Answer : ANSWER : A Explanation: let speed of boat and stream be 2x and x respectively So downstream speed = 2x+x = 3x, and upstream speed = 2x-x = x Let total distance between points is d km So he covered d ... with speed 3x = 48 km/hr(downstream) So time is 80/36 * 60 = 133.33 minutes = 2hr 13mins

A boat takes 38 hrs for travelling downstream from point p to point q and coming back to a point r midway between p and q. If the velocity of the stream is 8 km/hr and the speed of the boat in still water is 28 km/hr. What is the distance between p and q? A) 720 B) 640 C) 510 D) 450

Description : A boat takes 38 hrs for travelling downstream from point p to point q and coming back to a point r midway between p and q. If the velocity of the stream is 8 km/hr and the speed of the boat in still water is 28 km/hr. What is the distance between p and q? A) 720 B) 640 C) 510 D) 450

Last Answer : ANSWER: A Explanation: Speed downstream = (28 + 8)km/hr = 36 km/hr Speed upstream = (28 – 8)km/hr = 20 km/hr Let the distance between p and q be ‘x’km Then, x/36 + (x/2)/20 = 38 x/36 +x/40 = 38 19x = 13680 X = 720 km Therefore the distance between p and q is 720km

There are 3 poles M, N and O in a straight line such that point N is equidistant from points M and O. A boat can travel from point M to O downstream in 6 hours and from N to M upstream in 4 hours. Find the ratio of boat in still water to speed of stream. A) 2:3 B) 7:1 C) 3:2 D) 1:7

Description : There are 3 poles M, N and O in a straight line such that point N is equidistant from points M and O. A boat can travel from point M to O downstream in 6 hours and from N to M upstream in 4 hours. Find the ratio of boat in still water to speed of stream. A) 2:3 B) 7:1 C) 3:2 D) 1:7

Last Answer : ANSWER: B Explanation: Let speed in still water = x km/hr, of current = y km/hr Downstream speed = (x+y) km/hr Upstream speed = (x - y) km/hr Let MO = 2p km. So MN = NO = p km.  So 2p/(x+y) = 6 --------1  p/ ... - 2y) = 6x + 6y  8x - 8y = 6x +6y  2x = 14y  x/y = 14 / 2 = 7/1  x : y = 7 :1

If Nishu can swim downstream at 6kmph and upstream at 2kmph.What is his speed in still water ? A.5 km/hr B.4 km/hr C.8km/hr D.7km/hr

Description : If Nishu can swim downstream at 6kmph and upstream at 2kmph.What is his speed in still water ? A.5 km/hr B.4 km/hr C.8km/hr D.7km/hr

Last Answer : Answer- B Basic Formula: If the speed downloadstream is a km/ hr and the speed upstream is b km/ hr then Speed in still water is = ½ (a+b) km / hr [memory tool last 2 L cross and make +] Explanation: Given ... still water = ½ (a+b) kmph = ½ (6+2) = 8/2 = 4kmph speed in still water = 4kmph

A motorboat can cover 80 km upstream and 120 km downstream together in 26 hours. Also it can cover 100 km upstream and 144 km downstream together in 32 hours. What is the speed of the motorboat in still water? A) 12 km/hr B) 15km/hr C) 8.5km/hr D) 19km/hr

Description : A motorboat can cover 80 km upstream and 120 km downstream together in 26 hours. Also it can cover 100 km upstream and 144 km downstream together in 32 hours. What is the speed of the motorboat in still water? A) 12 km/hr B) 15km/hr C) 8.5km/hr D) 19km/hr 

Last Answer : ANSWER :C Explanation:  Upstream speed in both cases is 80 and 100.  Ratio is 80 : 100 = 8:10 = 4 : 5.  So let times in both cases be 4x and 5x  Downstream speed in both cases is 120 and 144 resp.  Ratio is ... 12 km/hr  So speed of boat = 1/2 * (5+12) =17/2km/hr  speed of boat = 8.5 km/hr

A motor boat sails 30 km of a river towards upstream in 10hrs. How long will it take to cover the same distance downstream, if the speed of the current is ½ of the speed of the boat in still water. A) 1.8hrs B) 3.33hrs C) 5hrs D) None of these

Description : A motor boat sails 30 km of a river towards upstream in 10hrs. How long will it take to cover the same distance downstream, if the speed of the current is ½ of the speed of the boat in still water. A) 1.8hrs B) 3.33hrs C) 5hrs D) None of these

Last Answer : ANSWER : B  Explanation:  Upstream speed = x –y  Downstream speed = x + y  x– y = 30/10 = 3km/hr  Again x = 2y  Therefore x – y = 3  y= 3km/hr ; x = 6km/hr  Therefore x + y = 9 km/hr  Time during downstream = 30/9 = 3.33hrs

There are two points on a highway a,b. They are 70 km apart. An auto starts from A and another auto starts from B simultaneously. If they travel in the same direction, they meet in 7 hours, but if they travel towards each other they meet in 1 hour. Find how fast the two autos are -Maths 10th

Description : There are two points on a highway a,b. They are 70 km apart. An auto starts from A and another auto starts from B simultaneously. If they travel in the same direction, they meet in 7 hours, but if they travel towards each other they meet in 1 hour. Find how fast the two autos are -Maths 10th

Last Answer : When they travel in same direction, suppose they meet when B travels for x m, then A will have travelled 70+x m in the same time Since, Speed =TimeDistance Speed of auto at A =7x+70 And Speed of auto at B =7x ... So, Speed of auto at A =7x+70 =7280 =40km/hr Speed of auto at B =7x =7210 =30km/hr

At the same speed a boat travelling 50km upstream and 78km downstream in 16hrs. Also it can travel 70km upstream and 104km downstream, in 22hrs at the same speed of the stream is. A) 5km/hr B) 3km/hr C) 4km/hr D) 2km/hr

Description : At the same speed a boat travelling 50km upstream and 78km downstream in 16hrs. Also it can travel 70km upstream and 104km downstream, in 22hrs at the same speed of the stream is. A) 5km/hr B) 3km/hr C) 4km/hr D) 2km/hr

Last Answer : ANSWER : C

A boat goes 3.5km upstream in 24 mins and the speed of the stream is 1.5km per hour, then the speed of the boat in still water is. A) 4.3 km/hr B) 7.4 km/hr C) 5.2km/hr D) 10.25km/hr

Description : A boat goes 3.5km upstream in 24 mins and the speed of the stream is 1.5km per hour, then the speed of the boat in still water is. A) 4.3 km/hr B) 7.4 km/hr C) 5.2km/hr D) 10.25km/hr

Last Answer : ANSWER: D  Explanation:  Speed of upstream = 3.5 / 24 km/min  = 3.5 / 24 * 60 km/hr = 8.75 km/hr  Speed of the stream = ½ (a - b)km/hr = 1.5 km/hr  1.5 = ½ ( a- 8.75)km/hr  a = 11.75 km/hr ... (a + b) km/hr  = ½ (11.75 + 8.75) = ½(20.5)  The speed of the boat in still water = 10.25 km/hr

Sakthi rows a boat at 4 km upstream in 1hour and 1 km downstream in 20 minutes. How long will he take to reach 3.5km in still water? A) 1 B) 2 C) 3 D) 4

Description :  Sakthi rows a boat at 4 km upstream in 1hour and 1 km downstream in 20 minutes. How long will he take to reach 3.5km in still water? A) 1 B) 2 C) 3 D) 4

Last Answer : ANSWER:A Explanation: Upstream Speed = 4/1 = 4km/hr Downstream Speed = 1/20 = 0.05 km/min = 0.05*60 = 3 km/hr Hence, speed of boat = 1/2( Upstream Speed + Downstream Speed) = 1/2 (4+3 ... , the time required to reach the distance of 3.5 km=DistanceCovered/Speed of boat = 3.5/3.5km/hr =1 km/hr

If a boy rows 8 km downstream in 6 hours and 4 km upstream in 4 hours then how long will he take to cover 16 km in stationary (still) water? A) 8 B) 14 C) 22 D) 16

Description : If a boy rows 8 km downstream in 6 hours and 4 km upstream in 4 hours then how long will he take to cover 16 km in stationary (still) water? A) 8 B) 14 C) 22 D) 16 

Last Answer : Answer: B Explanation: Distance covered in downstream = 8 km Time taken in downstream = 6 hours. Rate of downstream = 8/6=4/3 km/hr Distance covered in upstream = 4 km Time taken in upstream = 4hours. ... 3+1) = 7/6km/hr Time Taken to cover 16 km in still water = 16*6/7=14hrs (approximately)

A boat man lakes 5hrs 30 mins to row a boat 30km downstream of a river and 4 hrs 15mints to cover a distance of 10km upstream. Find the speed of the river current in km/hr. A) 1.5 km/hr B) 3km/hr C) 5km/hr D) 7 km/hr

Description : A boat man lakes 5hrs 30 mins to row a boat 30km downstream of a river and 4 hrs 15mints to cover a distance of 10km upstream. Find the speed of the river current in km/hr. A) 1.5 km/hr B) 3km/hr C) 5km/hr D) 7 km/hr

Last Answer : ANSWER: A  Explanation:  Rate downstream = (30 / 5 ½ ) km/hr  = 30 / (11/2) km/hr  = 30 * 2 / 11 km/hr = 60/11 km/hr  Rate upstream = (10 / 4 ¼)km/hr  = 10 / (17/4)km/hr  = 10 * 4 / 17 km/hr = ...  Speed of current = 1 / 2 (a - b) km/hr  =1 / 2 (60 / 11 - 40 / 17)  = 1.5 km/hr (approx.)

A motorboat running upstream takes 4 hrs 24 mins to cover a certain distance, while it takes 2hrs to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively? A) 8:3 B) 5:2 C) 3:7 D) 2:4

Description : A motorboat running upstream takes 4 hrs 24 mins to cover a certain distance, while it takes 2hrs to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively? A) 8:3 B) 5:2 C) 3:7 D) 2:4

Last Answer : ANSWER : A Explanation: Let the man's rate upstream be x'km/hr and downstream be y'km/hr Then distance covered upstream by 4hrs 24mints = distance covered by downstream in 2hrs (x * 4 2/5) = y *2 22x/5 = 2y Y = ... = (y+x/2) : (y -x/2) = 16x/10 : 6x/10 = 16x : 6x = 8:3

A man goes 4km upstream of the stream in 2hr and goes 2km downstream of the stream in 20mints. How long will it take to go 10km in stationary water? A) 1hr 15mits B) 2hrs 30mints C) 5hrs 30mints D) 3hrs 45mints

Description : A man goes 4km upstream of the stream in 2hr and goes 2km downstream of the stream in 20mints. How long will it take to go 10km in stationary water? A) 1hr 15mits B) 2hrs 30mints C) 5hrs 30mints D) 3hrs 45mints

Last Answer : ANSWER : B Explanation:  Rate downstream = (2/20 * 60) km/hr  = 6 km/hr  Rate upstream = 2 km/hr  Speed in still water = ½(6+2)km/hr  = 4 km/hr  Required time = distance / speed  = (10/4) hrs =(5/2)hrs =2 ½ hrs = 2hrs 30mits.

A boat travels 20 kms upstream in 6 hours and 18 kms downstream in 4 hours. Find the speed of the boat in still water and the speed of the water current? (a) 1/2 kmph (b) 7/12 kmph (c) 5 kmph (d) none of these

Description : A boat travels 20 kms upstream in 6 hours and 18 kms downstream in 4 hours. Find the speed of the boat in still water and the speed of the water current? (a) 1/2 kmph (b) 7/12 kmph (c) 5 kmph (d) none of these

Last Answer : (b) 7/12 kmph

Mohana can row 80km upstream and 110km downstream in 26 hrs. Also she can 60km upstream and 88km downstream in 20 hrs. Find the speed of the girl in still water and the speed of the current in ratio: A) 5:6 B) 3:6 C) 7:9 D) 8:3

Description : Mohana can row 80km upstream and 110km downstream in 26 hrs. Also she can 60km upstream and 88km downstream in 20 hrs. Find the speed of the girl in still water and the speed of the current in ratio: A) 5:6 B) 3:6 C) 7:9 D) 8:3 

Last Answer : ANSWER : D Explanation: Let rate upstream = x' km/hr and  Rate downstream = y' km/hr  Then 80/x + 110/y = 26 ---1  60/x + 88/y = 20--2  By solving 1 and 2  y= 11 ; x = 5  Rain in still water ... 5) km/hr = 8 km/hr  Rain of current = ½ (11 - 50) km/hr = 3 km/hr  The required answer is 8:3

A pedal boat goes 12km upstream and 14km downstream in 3hrs. It goes 15km upstream and 10.5km downstream in 3 hrs 15mints. The speed of the boat in still water is A) 10 B) 15 C) 20 D) 25

Description : A pedal boat goes 12km upstream and 14km downstream in 3hrs. It goes 15km upstream and 10.5km downstream in 3 hrs 15mints. The speed of the boat in still water is A) 10 B) 15 C) 20 D) 25 

Last Answer : ANSWER: A

If the speed of boat is 5 km/hr and speed of stream is 2 km/hr. What is the speed of the boat in Upstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Description : If the speed of boat is 5 km/hr and speed of stream is 2 km/hr. What is the speed of the boat in Upstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Last Answer : d) 3km/hr

If the speed of the boat is 5 km/hr and the speed of stream is 2 km/hr, what is the speed of the boat Downstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Description : If the speed of the boat is 5 km/hr and the speed of stream is 2 km/hr, what is the speed of the boat Downstream? a) 5km/hr b) 2km/hr c) 7km/hr d) 3km/hr

Last Answer : c) 7km/hr

A man rows 750m in 775 seconds against the stream and returns in 7 1/2 minutes. What is rowing speed in still water ? A.4.7km/hr B. 4km/hr C.3.5km/hr D.6km/hr

Description : A man rows 750m in 775 seconds against the stream and returns in 7 1/2 minutes. What is rowing speed in still water ? A.4.7km/hr B. 4km/hr C.3.5km/hr D.6km/hr

Last Answer : Answer-A Basic Formula: i) Speed in still water = ½ (a+b) kmph where a' is speed downstream and b' is speed upstream ii) a km / hr = a x 5/18 m /s iii) a m/sec = a x 18/5 km/hr Explanation: Speed upstream b' ... (750/450 + 750/675 ) x 18/5 km/hr = ½ (5/3 + 30/31) x 18/5 km/hr = 4.7 km/hr

A boy rows 1500m in 1350 seconds against the stream and returns in 15 minutes. His rowing speed in still water is. A) 5km/hr B) 4km/hr C) 7km/hr D) 9km/hr

Description : A boy rows 1500m in 1350 seconds against the stream and returns in 15 minutes. His rowing speed in still water is. A) 5km/hr B) 4km/hr C) 7km/hr D) 9km/hr

Last Answer : ANSWER : A  Explanation:  Rate upstream = (1500 / 1350) m/s = (150/135) m/s = 10/9 m/s  Rate downstream = (1500 / 900)m/s = (15/9)m/s  = 5/3 m/s  Rate in still water = ½ [ a+ b]  = ½[10 / 9 + 5 /3 ... +15 / 9]  = ½[25/9]  = 25/18 m/s  = (25/18) * (18/5)km/hr  speed in still water = 5km/hr

A boat covers 12 km upstream and 18km downstream in 3hrs while it covers 18 km upstream and 12km downstream in 3 ¼ hrs the velocity of the the boat upstream and downstream? A) 4,8 B) 8,12 C) 12,16 D) 3,9

Description : A boat covers 12 km upstream and 18km downstream in 3hrs while it covers 18 km upstream and 12km downstream in 3 ¼ hrs the velocity of the the boat upstream and downstream? A) 4,8 B) 8,12 C) 12,16 D) 3,9 

Last Answer : ANSWER : B 

Find the distance between the following pairs of points: (i) (2, 3), (4, 1) (ii) (-5, 7), (-1, 3) (iii) (a, b), (- a, – b) -Maths 10th

Description : Find the distance between the following pairs of points: (i) (2, 3), (4, 1) (ii) (-5, 7), (-1, 3) (iii) (a, b), (- a, – b) -Maths 10th

Last Answer : Distance between two points (x1 ,y1 ) and (x2 ,y2 ) is (x1 −x2 )2+(y1 −y2 )2 (i) Distance between(2,3) and (4,1) is =(2−4)2+(3−1)2 =(−2)2+(2)2 =4+4 =8 =22 (ii) Distance between (−5,7) and (−1,3) ... 42 (iii )Distance between (a,b) and(−a,−b) is =(a−(−a))2+(b−(−b))2 =(2a)2+(2b)2 =4a2+4b2 =2a2+b2

Check whether the following are quadratic equations: (i) (x+ 1)2=2(x-3) (ii) x – 2x = (- 2) (3-x) (iii) (x – 2) (x + 1) = (x – 1) (x + 3) (iv) (x – 3) (2x + 1) = x (x + 5) (v) (2x – 1) (x – 3) = (x + 5) (x – 1) (vi) x2 + 3x + 1 = (x – 2)2 (vii) (x + 2)3 = 2x(x2 – 1) (viii) x3 -4x2 -x + 1 = (x-2)3 -Maths 10th

Description : Check whether the following are quadratic equations: (i) (x+ 1)2=2(x-3) (ii) x - 2x = (- 2) (3-x) (iii) (x - 2) (x + 1) = (x - 1) (x + 3) (iv) (x - 3) (2x + 1) = x (x + 5) (v) (2x - 1) (x - 3) = (x ... vi) x2 + 3x + 1 = (x - 2)2 (vii) (x + 2)3 = 2x(x2 - 1) (viii) x3 -4x2 -x + 1 = (x-2)3 -Maths 10th

Last Answer : this is the correct answer!

How many solutions does the pair of equations y = 0 and y = -5 have? -Maths 10th

Description : How many solutions does the pair of equations y = 0 and y = -5 have? -Maths 10th

Last Answer : y = 0 and y = -5 are Parallel lines, hence no solution.

2. Show that any positive odd integer is of the form 6q + 1, or 6q + 3, or 6q + 5, where q is some integer. -Maths 10th

Description : 2. Show that any positive odd integer is of the form 6q + 1, or 6q + 3, or 6q + 5, where q is some integer. -Maths 10th

Last Answer : Let a be any positive integer and b = 6. Then, by Euclid’s algorithm, a = 6q + r, for some integer q ≥ 0, and r = 0, 1, 2, 3, 4, 5, because 0≤r

Show that any positive odd integer is of the form 6q + 1, or 6q + 3, or 6q + 5, where q is some integer. -Maths 10th

Description : Show that any positive odd integer is of the form 6q + 1, or 6q + 3, or 6q + 5, where q is some integer. -Maths 10th

Last Answer : Let a' be any positive integer and b = 6. ∴ By Euclid's division algorithm, we have a = bq + r, 0 ≤ r ≤ b a = 6q + r, 0 ≤ r ≤ b [ ∵ b = 6] where q ≥ 0 and r = 0,1, 2, 3, 4, ... numbers. Therefore, any odd integer can be expressed is of the form 6q + 1, or 6q + 3, or 6q + 5 where q is some integer

Is polynomial y4 + 4y2 + 5 have zeroes or not? -Maths 10th

Description : Is polynomial y4 + 4y2 + 5 have zeroes or not? -Maths 10th

Last Answer : Y4+4y2+5=y4+4y2+4 +1 =(y2+2)2+1 The first term being square,it will be equal to zero or greater than zero. Therefore (y2+2)2+1 will not be zero for any value of y. Therefore given polynomial have no zeroes.

Find the distance between the points (-8/5, 2) and (2/5, 2). -Maths 10th

Description : Find the distance between the points (-8/5, 2) and (2/5, 2). -Maths 10th

Last Answer : answer:

Find a point on the y-axis equidistant from (-5, 2) and (9, -2). -Maths 10th

Description : Find a point on the y-axis equidistant from (-5, 2) and (9, -2). -Maths 10th

Last Answer : answer:

A calf is tied with a rope of length 6 m at the corner of a square grassy lawn of side 20 m. If the length of the rope is increased by 5.5 m, find the increase in area of the grassy lawn in which the calf can graze. -Maths 10th

Description : A calf is tied with a rope of length 6 m at the corner of a square grassy lawn of side 20 m. If the length of the rope is increased by 5.5 m, find the increase in area of the grassy lawn in which the calf can graze. -Maths 10th

Last Answer : Given, The initial length of the rope = 6 m Then the rope is said to be increased by 5.5m So, the increased length of the rope = (6 + 5.5) = 11.5 m We know that, the corner of the lawn is a quadrant of a circle. Thus ... – 62) = 1/4 x 22/7 (132.25 – 36) = 1/4 x 22/7 x 96.25 = 75.625 cm2

At �t� minutes past 2 pm, the time needed by the minute hand of a clock to show 3 pm was found to be 3 minutes less than minutes. Find ‘t’. -Maths 10th

Description : At �t� minutes past 2 pm, the time needed by the minute hand of a clock to show 3 pm was found to be 3 minutes less than minutes. Find ‘t’. -Maths 10th

Last Answer : answer:

Aftab tells his daughter, “Seven years ago, I was seven times as old as you were then. Also, three years from now, I shall be three times as old as you will be.” (Isn’t this interesting?) Represent this situation algebraically and graphically. -Maths 10th

Description : Aftab tells his daughter, “Seven years ago, I was seven times as old as you were then. Also, three years from now, I shall be three times as old as you will be.” (Isn’t this interesting?) Represent this situation algebraically and graphically. -Maths 10th

Last Answer : Then , seven years ago, Aftab's age = x − 7 His daughter's age = y − 7 According to the question, x − 7 = 7 ( y − 7 ) x − 7 = 7 y − 4 9 x − 7 y = − 4 9 + 7 x − 7 y = − 4 2 ( ... these two equations x − 7 y = − 4 2 ⟹ x = 7 y − 4 2 x = 7 y − 4 2 4 2 3 5 4 9 y 1 2 1

The coach of a cricket team buys 3 bats and 6 balls for Rs 3900. Later, she buys another bat and 2 more balls of the same kind for Rs 1300. Represent this situation algebraically and geometrically. -Maths 10th

Description : The coach of a cricket team buys 3 bats and 6 balls for Rs 3900. Later, she buys another bat and 2 more balls of the same kind for Rs 1300. Represent this situation algebraically and geometrically. -Maths 10th

Last Answer : Step-by-step explanation: Let x be the cost of 1 bat Let y be the cost of 1 ball Cost of 3 bats = 3x Cost of 6 balls = 6y Cost of 3 balls = 3y The coach of a cricket team buys 3 ... 6 balls for ₹ 3900 She buys another bat and 3 more balls of the same kind for ₹1300. So, situation algebraically :