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 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 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 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
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
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 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.
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
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 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
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 : 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
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
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
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.)
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
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 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
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 : 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
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 : If the boat goes 21 km downstream, What is the time required to cover it? a) 5 hrs b) 2 hrs c) 7 hrs d) 3 hrs
Last Answer : d) 3 hrs
Description : Kishore is travelling on his bike and has calculated to reach point P at 4 pm if he travels at 20 kmph. He will reach there at 12 noon if he travels at 30 kmph. At what speed must he travel to reach P at 2 pm? a) 18 kmph b) 12 kmph c) 24 kmph d) 16 kmph
Last Answer : C Let the distance be x km Travelling at 20 kmph, Kishore will reach point P at 4pm. Travelling at 30 kmph, Kishore will reach point P at 12noon. Therefore, time taken when travelling at 20km - ... his travelling time must be (12-2)=10 hours Hence, required speed =240/10=24 kmph
Description : A motor car starts with the speed of 70 km/hr with its speed increasing every two hours by 10 kmph. In how many hours will it cover 345 kms? A.4 hrs B.4 hrs 5 mins C.4 1/2 hrs D.2 hrs E.None of these
Last Answer : Answer - C (4 1/2 hrs) Explanation - Distance covered in first 2 hours = (70 x 2) km = 140 km Distance covered in next 2 hours = (80 x 2) km = 160 km Remaining distance = 345 - (140 + 160) = 45 km. Speed in the ... ..1 hr 45km .? ?=45/90hr=1/2hr Total time taken = 2 + 2 +1/2=4 (1/2)hrs
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 : 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)
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
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
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 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
Last 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 = ... 40x = 400 - 80x 120x = 200 x = 200 120 = 5/3 The speed of the stream is 5/3 km/h
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
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 flag pole 18 m high casts a shadow 9.6 m long. Then the distance of the top of the pole from the far end of the shadow is (a) 25.6 (b) 20.4 (c) 23.7 (d) 32.5
Last Answer : (b) 20.4
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.
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
Description : A train starts from Delhi and reaches Lucknow in 24.5 hours. If it travels the first half of journey at 30 kmph and second half at 40 kmph then what is the total distance it travelled? 1) 750 km 2) 800 km 3) 840 km 4) 900 km 5) 920 km
Last Answer : 3) 840 km
Description : Mr.Aneesh left for city 1 from city 2 at 3.00 pm. He travelled at the speed of 60km/hr for 1 and half hours. After that the speed was reduced to 15 km/hr. If the distance between two cities is 120 kms, at what time did Mr.Aneesh reach city 1 ? a) 6.30 pm. b) 5.30 pm. c) 7.30 pm. d) 8.30 pm.
Last Answer : A Mr.Aneesh travelled 60 km/hr for 1 1/2 hours (3/2 hours). Distance covered in 3/2 hours = 60 x 3/2 = 90 km. Therefore, remaining distance = 120 -90 = 30 km After 3/2 hours, the speed was ... village 2 at 3.00 pm + 3 hours 30 minutes = 6.30pm Hence the required answer is 6.30 pm.
Description : Two persons of masses 55 kg and 65 kg respectively, are at the opposite ends of a boat. The length of the boat is 3.0 m and weighs 100 kg. The 55 kg man walks up to the 65 kg man and sits with him. If the boat is in still water the centre of mass of the system shifts by
Last Answer : (4) zero
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
Last Answer : e Suppose they meet z hours after 6 a.m. Distance covered by X in z hours = 25× z km. Distance covered by Y in (z - 2) hours = 35(z - 2) km. Therefore 25z + 35(z- 2) = 170 60z = 240 x = 4. So, they meet at 10 a.m.
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 : The speed of a car increases by 2 kms after every one hour. If the distance travelled in the first one hour was 35 kms, what was the total distance traveled in 12 hours? A.456 kms B.482 kms C.552 kms D.556 kms E.None of these
Last Answer : Answer – C (552 kms) Explanation – Total distance travelled in 12 hours = (35 + 37 + 39 + …… upto 12 terms) This is an A.P. with first term, a = 35, number of terms, n = 12, common difference, d =2. Required distance =12/2 (2 x 35 + (12 – 1) x 2) = 6(70 + 22) = 552 kms
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
Last Answer : Let Abhay's speed be x km/hr. Then, 30/x-30/2x= 3 6x = 30 x = 5 km/hr. Answer: a)
Description : Thirty men take 20 days to complete a job working 9 hours a day. How many hour a day should 40 men work to complete the job? (a) 8 hrs (b) 7 1/2 hrs (c) 7 hrs (d) 9 hrs
Last Answer : (b) 7 1/2 hrs
Description : There is a circular path around a sports field. Priya takes 18 minutes to drive one round of the field. Harish takes 12 minutes. Suppose they both start at the same point and at the same time and go in the same ... will they meet ? (a) 36 minutes (b) 18 minutes (c) 6 minutes (d) They will not meet
Last Answer : (a) 36 minutes
Description : The area of the circle that can be inscribed in a square of side 6 cm is (a) 36 π cm 2 (b) 18 π cm 2 (c) 12 π cm 2 (d) 9 π cm 2
Last Answer : (d) 9 π cm 2
Description : What is the missing number in this series? 8 2 14 6 11 ? 14 6 18 12
Last Answer : Answer: 9
Description : A person travels from P to Q at a speed of 40 kmph and returns by increasing his speed by 50%. What is his average speed for the both the trips? A.35 kmph B.4o kmph C.48 kmph D.55 kmph E.None of these
Last Answer : Answer – C (48 kmph) Explanation – Speed on return trip = 150% of 40 = 60 kmph Average speed = [2 x 40 x 60] / [40 + 6]km/hr =4800/100km/hr = 48 km/hr.
Description : A certain thing is thrown twice from a place with the gap of 45 minutes between the two shots. A girl approaching this point in a train heard the second shot 44 minutes after she heard the first shot. What is the speed of train ... travels at 660 m/s? a) 62 km/hr b) 54 km/hr c) 48 km/hr d) 27 km/hr
Last Answer : B Actual time between the two shots being fired = 45 minutes. If a girl was stationary she would have heard the shots after 44 minutes. But since the train was moving towards the source, she heard the second shot after ... = (15 *18/5) km/hr =54 km/hr Hence the speed of the train is 54 km/hr