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

1 Answer

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

Related questions

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

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

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

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

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

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

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)

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

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

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

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

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.

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

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

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

Description : A man rows to a place 48km distant and back in 14 hours. He finds that he can row 4km with the stream in the same time as 3km against the stream. Find the rate of the stream. A.2 km/hr B.1 km/hr C.3 km/hr D.3.5km/hr

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Description : Two stations X and Y are 170 km apart on a straight line. One train starts from X at 6 a.m. and travels towards Y at 25 kmph. Another train starts from Y at 8 a.m. and travels towards X at a speed of 35 kmph. At what time will they meet? a) 11. 30 a.m b) 10.30 a.m c) 11 a.m d) 9 a.m e) 10 am

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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

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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

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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

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Description : Speed of a boat in standing water is 9kmph and the speed of the stream is 1.5kmph. A man rows to a place at a distance of 10.5 km and comes back to the starting point. Find the total time taken by him. A.24 hours B.16 hours C.20 hours D.15 hours

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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.

Description : A boat cover a certain distance downstream in 2hr while it comeback 3/2hrs.If the speed of the stream be 4kmph.what is the speed of the boat in still water? 1)21kmph 2)18kmph 3)22kmph 4)12kmph

Last Answer : 1)21kmph Exp:(x+3) ×2=(x-3)(3/2)=>21.

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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

Description : P walks around a circular field at the rate of two rounds per hour while Q runs around it at the rate of eight rounds per hour. They start in the opposite direction from the same point at 6.45 a.m. They shall first cross each other at? a) 6.45 a.m b) 6.50 a.m c) 7.51 a.m d) 6.51 a.m e) 7.45 am

Last Answer : d Since P and Q move in the opposite direction along the circular field, so they will first meet each other when there is a difference of one round between the two. Relative speed of P and Q = 8+2 = 10 rounds per hour. Time ... 1/10 hr = 6 min. 6 Hrs 45 min + 6 min = 6 hrs 51 min i.e, 6.51 a.m

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 

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Last Answer : (a) 3.5 km/h

Description : In covering a distance of 30 km, Abhay takes 2 hours more than Sameer. If Abhay doubles his speed, then he would take 1 hour less than Sameer. Abhay's speed is? a) 5 kmph b) 6 kmph c) 6.25 kmph d) 7.5 kmph e) None of these

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Description : Kathir and Anand can do a work in 20 days and 30 days respectively. Kathir started the work and left after 4 days. Anand took over and completed the work. In how many days was the total work completed? a) 28 days b) 20 days c) 23 days d) 25 days e) 26 days 

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Description : A pedal boat can cover 20km in 1 hr in still water. And it takes thrice as much as time to cover up than as to cover down the same distance in running water. The speed of the current is. A) 7.5 km/hr B) 20 km/hr C) 5 km/hr D) 10 km/hr

Last Answer : ANSWER : D Explanation: Let the speed of upstream be x' km/hr Then speed in downstream = 3x km/hr[thrice as much as time to cover up than as to cover down the same distance in running water] Speed in ...  Speed in downstream = 30 km/hr  Hence speed of the current = (30 -10)/2  = 10 km/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

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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

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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

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Description : On selling 25 balls at Rs. 1015, there is a profit equal to the cost price of 10 balls. What is the cost price of a ball? a) Rs. 31 b) Rs. 29 c) Rs. 35 d) Rs. 27 e) Rs. 39

Last Answer : b Profit = (S.P of 25 balls) - (C.P of 25 balls) = 1015 - (C.P of 25 balls) Given that Profit = (C.P of 10 balls) => 1015 - (C.P of 25 balls) = (C.P of 10 balls) => (C.P of 25 balls) + (C.P of 10 balls) = 1015 => C.P of 35 balls = 1015 => C.P of 1 ball=1015 / 35 = Rs. 29

Description : Madhan was 3 times as old as his daughter 10 years ago. After 10 years, Madhan will be twice as old as his daughter. Find out the present age of Madhan. a) 68 years b) 70 years c) 40 years d) 55 years e) 80 years

Last Answer : b Let age of the daughter before 10 years = x Then, age of Madhan before 10 years = 3x After 10 years, Madhan will be twice as old as his daughter. ⇒ 3x + 20 = 2( x+20) ⇒ x = 20 ⇒ Present age of Madhan = 3x + 10 = 3× 20+ 10 = 70 years.

Description : Distance between two stations P & Q is 1556km. A passenger train covers the journey from P to Q at 168km per hr and return back to P with a uniform speed of 112km/hr. Find the Average speed of the train during the whole journey? A) 124.4 km/hr B) 130.4km/hr C) 134.4 km/hr D) 130.0 km/hr

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Description : 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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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 

Description : Arun started a business with Rs. 40,000 and is joined afterwards by Arul with Rs.60, 000. After how many months did Arul join if the profits at the end of the year are divided equally? a) 3 b) 4 c) 5 d) 6 e) 2

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Description : Three pipes P, Q and R can fill a tank from empty to full in 40 minutes, 15 minutes, and 30 minutes respectively. When the tank is empty, all the three pipes are opened. P, Q and R discharge chemical solutions X, Y and Z respectively. ... 5 minutes? a) 8 / 15 b) 7 / 15 c) 8 / 17 d) 6 / 13 e) 8 / 13

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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 

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Description : A letter lock consists of four rings each marked with five different letters. The number of distinct unsuccessful attempts to open the lock is at the most -. a) 625 b) 676 c) 576 d) 624 e) 575

Last Answer : d Since each ring consists of five different letters, the total number of attempts possible with the four rings is =5 * 5 * 5 * 5 = 625. Of these attempts, one of them is a successful attempt. Maximum number of unsuccessful attempts = 625 - 1 = 624.

Description : Simple interest on a certain sum of money for 4 years at 5% per annum is half the compound interest on Rs. 8000 for 2 years at 10% per annum. The sum placed on simple interest is: a) Rs.4200 b) b)Rs.4250 c) Rs.5250 d) Rs.5200 e) Rs.4000

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Description : There is road besides a river. Two friends started from a place P, moved to a shopping mall situated at another place Q and then returned to P again. One of them moves on a cycle at a speed of 12 km/ ... which of the two friends will return to place P? A. Both B. Boater C. Cyclist D. None of these 

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Description : A mototboat can row to a place 112 km away and come back in 44 hours. The time to row 42 km with the stream is same as the time to row 24 km against the stream. Find the speed of boat in still water. A) 5.5 km/hr B) 7.5km/hr C) 10.5 km/hr D) 3.5 km/hr 

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Description : A man can row 9 (1/3) kmph in still water and finds that it takes him thrice as much time to row up than as to row down the same distance in the river. What is speed of the current ? A. 5km/hr B.3(1/2) km/hr C.4 (2/3) km/hr D.8 (3/2)km/hr

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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

Description : A fisherman rows to a place 24km distance and back in 7 hours. He finds that he can row 2km with the stream in the same time 1.5 km against the stream.The rate of the stream is? A) 7 B) 5 C) 3 D) 1 

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