A car travels at a speed of 50 km/hr for 30 minutes, at 30 km/hr for next 15 minutes and then 70 km/hr for next 45 minutes.

1 Answer

Answer :

A car travels at a speed of 50 km/hr for 30 minutes, at 30 km/hr for next 15 minutes and ... next 45 minutes. What is the average speed of the car?

Related questions

Description : Anitha travels 400 km by bus at 70 km/hr, 600 km by train at 80km/hr, 250 km by bike at 60 km/hr and 50 kn by car at 40 km/hr. what is the average speed for the total distance? a) 68.45 b) 69.45 c) 67.45 d) 69.77

Last Answer : D Total distance = (400+250+50+600)km =1300 km Total time taken = (400/70 + 600/80+250/60+50/40) hrs =(40/7 +60/8+25/6+5/4) =(24*40)+(21*60)+(28*25)+(42*5) / 168 =960+1260+700+210 / 168 =(3130 / 168) Average speed =(1300*168 / 3130) km/hr =218400/3130 =69.77 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

Description : A train travels between two stations 15 km apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform retardation, the maximum speed attained by the train during the journey will by a.125 km/hr b.107 dynes c.80 km/hr d.100 km/hr e.60 km/hr

Last Answer : d. 100 km/hr

Description : A train travels between two stations 15 km, apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform relardation, the maximum speed attained by the train, during, the journey, will be a.60 km/hr b.80 km/hr c.125 km/hr d.100 km/hr e.107 dynes

Last Answer : d. 100 km/hr

Description : Ganesh is travelling on his motorbike and has calculated to reach golden temple at 8 p.m if he travels at 30 km/hr; he will reach there at 6 p.m if he travels at 45 km/hr. At what speed must he travel to reach the golden temple at 7 p.m? a) 36 b) 46 c) 32 d) 30

Last Answer : A Let the distance travelled be x km x/30 – x/45 = 2 (3x – 2x) / 90 = 2 x/90 = 2 x = 180km Time taken to travel 180 km at 30 km/hr = 180 / 30 = 6 hrs So ganesh started 6 hrs before 8 pm That is 2 pm Required speed = distance / time =(180/5) =36 km/hr

Description : Ravi walks to and fro to a Gym. He spends 30 minutes in gym. If he walks at speed of 20 km an hour, he returns to home at 8.00 a.m. If he walks at 30 km an hour, he returns to home at 7.30 a.m. How fast must he walk in order to return at 7.15 hours? a) 40 km/hr b) 30 km/hr c) 60 km/hr d) 50 km/hr

Last Answer :  A As per the question, let D be the total distance and ‘t’ is the time taken. So we have: D=20t 20t =30(t-0.5) 20t=30t-15 10t=15 t=3/2 D= 30 km Now, for the condition given we have: 30=S(t-3/4) 30=S(3/2-3/4) 30=S((6-3)/4) 30=S(3/4) S=40 km/hr

Description : The distance between two cities A and B is 330 km. A train starts from A at 8 a.m. and travels towards B at 60 km/hr. Another train starts from B at 9 a.m. and travels towards A at 75 km/hr. At what time do they meet? A.10:30 am B.10:45 am C.11 am D.11:25 am E.None of these

Last Answer : Answer – C (11 am) Explanation – Suppose they meet x hrs after 8 a.m. Then, (Distance moved by first in x hrs) + [Distance moved by second in (x-1) hrs] = 330 60x + 75(x – 1) = 330 x = 3 So, they meet at (8 + 3), i.e. 11 a.m

Description : The distance between two cities A and B is 330 km. A train starts from A at 8 a.m. and travels towards B at 60 km/hr. Another train starts from B at 9 a.m. and travels towards A at 75 km/hr. At what time do they meet? A.10:30 am B.10:45 am C.11 am D.11:25 am E.None of these

Last Answer : Answer – C (11 am) Explanation – Suppose they meet x hrs after 8 a.m. Then, (Distance moved by first in x hrs) + [Distance moved by second in (x-1) hrs] = 330 60x + 75(x – 1) = 330 x = 3 So, they meet at (8 + 3), i.e. 11 a.m

Description : A bus starts at bus stop and reaches a destination in 4 hours. If it travels first and second half at the speed of 40 km/hr and 50 km/hr respectively then the distance between bus stop and destination is a) 177.7 km b) 154.2 km c) 163.5 km d) 147.3 km

Last Answer : A Let the distance between bus stop and destination be X. The total time taken by the bus to cover X = 4 hours Since X/2 by 40km/hr and remaining X/2 by 50km/hr Then by Time = distance/speed, we have ... = 1600 9X = 1600 X = 1600/9 = 177.7 Hence 177.7 km is the required answer.

Description : A girl covered a definite distance at same speed. Had she moved 6 km/hr faster, she would have taken 30 mins less. If she had moved 4 km/hr slower, she would have taken 30 mins more. The distance (in km) is. a) 50 b) 40 c) 70 d) 60

Last Answer : D Let distance = x km Rate = y km/hr x/y - x / (y+6) = 30/60 (x(y+6)-xy) / y(y+6) = ½ (xy +6x - xy) / y(y+6) = ½ 12x = y(y+6) ------------>1 And x/ (y-4) - x/y = 30/60 (Xy - x(y-4 ... = (y+6) / (y-4) 3y - 12 = 2y +12 Y = 24km Put y value in 1 we get 12x = 24 (24+6) 12x = 24 *30 X=60km

Description : A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is: a) 35.55 km/hr b) 36 km/hr c) 71.11 km/hr d) 71 km/hr e) 69.69km/hr

Last Answer : Total time taken = (160/64) + (160/80) = 9/2 hrs. Avg Speed – 320 × (2/9) km/hr = 71.11km/hr Answer: c)

Description : A bike starts with a speed of 60 km/hr at 8a.m. Due to the problem in engine it reduces its speed as 20 km/hr for every 1 hour. After 9 am, the time taken to covers 15 km is: a) 13 minutes and 20 seconds b) 15 minutes and 09 seconds c) 18 minutes and 15 seconds d) 22 minutes and 30 seconds

Last Answer : 15 min

Description : 2 pistol were shoot from the same place at an interval of 15 mins and 15 secs but a boy in the train approaching the place hears the second shot 15 mins after the first. The speed of the train(in km/hr),supposing that speed travels at 320 metres per second is. a) 15.166 b) 17.144 c) 18.563 d) 19.188

Last Answer : D Let the speed of the train be x m/sec Then distance travelled by the train in 15mins = distance travelled by sound in 15secs X*15*60 = 320*15 900x = 4800 X=4800/900 X=5.33 Speed of the train 5.33 m/s Convert m/s into km/hr 5.33m =(5.33*18/5) =(95.94/5) =19.188 km/hr

Description : kajal rides his scooter 14km at an average speed of 16 km/hr and again travels 16km at an average speed of 14 km/hr. What is her average speed for the entire trip approximately? a) 15.36 km/hr b) 17.46 km/hr c) 13.56 km/hr d) 14.86 km/hr

Last Answer : D Total distance travelled =14+16=30Km Time taken to travel 14 km at an average speed of 16 km/hr =14/16=7/8 Hr Time taken to travel 16 km at an average speed of 14 km/hr =16/14=8/7 hr Total time taken = ... /Total time taken =30/(7/8+8/7) =30/(113/56) =30*56/113=1680/113 =14.86 km/hr

Description : Anand takes 9 hours more than Babu to cover 150 km. Suppose the time taken by Anand is 30 minutes less than Babu he must double his speed. Then the speed of Anand will be: a) 7.64 km/hr. b) 7.43km/hr. c) 7.89 km/hr. d) 7.25 km/hr.

Last Answer : C Let Anand 's speed be X km/hr. And let the time taken by Babu be Y. Since Anand takes 9+Y hours to cross 150km at X km/hr. i.e., 150 / X = 9+Y ---eqn1 And he takes Y - 1/2 hours to cross 150km at 2X km ... )/ 2x = 19/2 150/2X =19/2 150/X = 19 X = 7.89 Hence Anand 's speed is 7.89 km/hr.

Description : If Gowtham ride a bike at 30 km/hr, then he arrives at a certain place at 3 p.m. If he ride at 45 km/hr, he will arrive at the same place at 1 P.m. At what speed must he ride to get there at noon? a) 18 km/hr b) 24 km/hr c) 36 km/hr d) 28 km/hr

Last Answer : C When speed of gowtham = 30 km/hr =d/t and, When speed of the gowtham = 45 km/hr =d/(t−2) Equating the value of d: 30t =45(t-2) 30t=45t-90 15t=90 t=6 hours Finally desired speed =d/(t-1) =30t/(t-1) =30*6/(6-1) =180/5 =36 km/hr

Description : Two bike A & B start at the same time from salem to Rasipuram which are 60km apart. If the 2 bikes travel in opposite directions, they meet after 1 hr and if they travel in same direction(from salem towards Rasipuram), then A meets B after 3 hrs. what is the speed of bike A? a) 50 b) 70 c) 90 d) 30

Last Answer : B Let their speed be x km/hr and y km/hr respectively Then 60 / (x+y) = ½ X+y = 120 ------------->1 Now when they move in same direction (distance travelled by A in 3 hrs) - (Distance travelled by B in ... = 140 X=70 Put x value in 1 we get Y=120 -70=50 Y=50 Therefore A's speed = 70 km/hr

Description : The distance between two cities A and B is 330km. A train starts from A at 8 (a)m. and travels towards B at 60 km/hr. Another train starts from B at 9 (a)m. and travels towards A at 75 km/hr. At what time do they meet? a) 10 am. b) 10 : 30 am. c) 11 am. d) 11 : 30 am. e) None of these

Last Answer : Distance travelled by first train in one hour = 60 x 1 = 60 km Therefore, distance between two train at 9 a.m. = 330 – 60 = 270 km Now, Relative speed of two trains = 60 + 75 = 135 km/hr Time of meeting of two trains =270/135=2 hrs. Therefore, both the trains will meet at 9 + 2 = 11 A.M. Answer: c)

Description : The distance between salem and trichy is 170 km. A bus starts from salem at 6 a.m. and travels towards trichy at 20 km/hr. Another bus starts from trichy at 7 a.m. and travels towards salem at 30 km/hr. At what time will they meet? a) 7a.m b) 8a.m c) 9a.m d) 10a.m

Last Answer : D Assume that they meet x hours after 6 a.m. Then, Bus 1, starting from salem, travels x hours till the bus meet. Distance travelled by bus 1 in x hours =20x km bus 2, starting from trichy , travels (x−1) hours ... +30=50x 200=50x X=4 Hence, the bus meet 4 hours after 6 a.m., i.e. at 10a.m

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 : A 250 m goods train takes 50 s to cross a person who is going in the same direction with the speed of 8 km/h. After crossing that person, the train can reach next station in 2 hr. How long that person takes to reach that station after being crossed by them? A) 2 ½ hr B) 5hr C) 3 1/2hr D) 1hr

Last Answer : ANSWER:A Explanation:  Speed of the person = 8 kmph  = (8*5/18)m/s  = 20/9 m/s  Then relative speed of train = (x-20/9)m/s  As train takes 50 sec to cross the person  Therefore 50 =250/(x-20/ ... 20,000 m  = 20 km Thus time taken by the person to cover the distance of 20km= 20/8 hr=2 ½ hr

Description : Karthiga jogs a speed of 18 km/hr at a distance of 27 km. at what speed would she need to jog during the next 4.5 hrs to have an average of 27km/hr for the entire jogging session. a) 40km/hr b) 30 km/hr c) 20 km/hr d) 35 km/hr

Last Answer : B Let the speed of jagging be x km/hr Total time taken = (27/18 hrs + 4.5 hrs) =(1.5 hrs + 4.5 hrs) =6 hrs Total distance covered = (27+4.5 x) km Therefore (27 +4.5x) / 6= 27 27+4.5x = 162 4.5x = 135 X=135/4.5 =30 So jagging speed is 30 km/hr

Description : A van travels from namakkal to Madurai at a constant speed. If its speed were increased by 40km/hr it would have taken 1 hr lesser to cover the distance. It would have taken further 45 mins lesser if the speed ... by 40km/hr. what is distance between the 2 cities. a) 1680 b) B1660 c) 1670 d) 1675

Last Answer : A Let distance = x km Usual rate = y km/hr Then x/y - x/(y+40) =1 X(y+40) / y(y+40) = 1 Xy+40x - xy = y(y+40) 40x = y(y+40) ---------->1 x/y - x/y+80 = 7/4 x(y+80) - xy / y(y+ ... (y+80) / y(y+40) 8(y+40) = 7y + 560 8y +320 = 7y+560 Y=240 Substitute y value in 1 40x = 240*280 X=1680 km

Description : Senthil started bike at 5 a.m to reach a temple. After going temple, his bike went out of order. Consequently he rested for 45 mins and came back to his house walking all the way. Senthil reached home at 8 a.m. if bike ... /hr, then on bike he covered a distance of. a) 3.12 b) 2.76 c) 4.13 d) 2.14

Last Answer : D Time taken = 2 hr 15 mins = 2 ¼ hrs Time = 9/4 hrs Let the required distance be x km Then x/20 + x/1 = 9/4 (X+20x) / 20 = 9/4 21x / 20 = 9/4 84x = 180 X= 2.14 km Therefore the required diatance is 2.14 km

Description : A taxi driver make a trip from the plains to ooty which are 340km apart at an average speed of 60km/hr. In the return trip, he covers the speed distance at an average of 30 km/hr. the average speed of the taxi over the entire distance of 680 km is a) 30 b) 40 c) 50 d) 60 

Last Answer : B Average speed =(2xy/( x+y)) km/hr Given x =60 km/hr y = 30km/hr Average speed = (2*60*30/ (60+30)) km/hr =(3600/ 90) =40 km/hr

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 : A car moves at a constant speed of 60 km/hr for 1 km and 40 km/hr for next 1 km. What is the average speed of the car?

Last Answer : A car moves at a constant speed of 60 km/hr for 1 km and 40 km/hr for next 1 km. What is the average speed of the car?

Description : What is the average speed in kmh for a car that travels 50.0 km in 40.0 min?

Last Answer : It is travelling at 75 kmph.

Description : A train overtakes two persons walking along a railway track. The first one walks at 4.5 km/hr. The other one walks at 5.4 km/hr. The train needs 8.4 and 8.5 seconds respectively to overtake them. What is the speed ... as the train? A.59 km/hr B.65 km/hr C.70 km/hr D.81 km/hr E. None of these

Last Answer : Answer-D (81 km/hr) Explanation4.5 km/hr =(4.5 x 5/18)m/sec =5m/4sec = 1.25 m/sec, and 5.4 km/hr =(5.4 x 5/18)m/sec =3m/2sec = 1.5 m/sec. Let the speed of the train be x m/sec. Then, (x - 1.25) ... - 12.75 => 0.1x = 2.25 => x = 22.5 Therefore Speed of the train =(22.5 x18 /5)km/hr = 81 km/hr.

Description : A man moevs with p km/h speed for 20 minutes and q km/h for next 30 minutes. Find the expression for this average speed in km/h.

Last Answer : A man moevs with p km/h speed for 20 minutes and q km/h for next 30 minutes. Find the expression for this average speed in km/h.

Description : A car travels 40 miles over 30 minutes. What is the average speed of the car during this time?

Last Answer : 80 miles/hour

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

Description : Busses start from a bus terminal with a speed of 20 km/hr at intervals of 10 minutes. What is the speed of a man coming from the opposite direction towards the bus terminal if he meets the buses at intervals of 8 minutes? a) 3 km/hr b) 4 km/hr c) 5 km/hr d) 7 km/hr e) None of these

Last Answer : Distance covered in 10 minutes at 20 kmph = distance covered in 8 minutes at (20+x) kmph 20× 10/60=8/60(20+x) 200 = 160 + 8x 8x = 40 x=40/8=5 kmph Answer: c)

Description : Tharun has to cover a distance of 84 km in 40 minutes. If he covers one-half of the distance in one-fourth of the total time, to cover the remaining distance in the remaining time, what should be his speed in km/hr? a) 42 km/hr b) 64km/hr c) 84km/hr d)76km/hr

Last Answer : C Tharun needs to cover 84 km in 40minutes Given that he covers one-half of the distance in one-fourth of the total time ⇒ he covers half of 84km in one-fourth of 40 minutes ⇒ He covers 42 km in ¼ * ... Distance =42km Time =30minutes =1/2 hr Required Speed = Distance / Time =42/(1/2)=84 km/hr

Description : A bus can travel 25% faster than a jeep. Both start from point P at the same time and reach point Q, 225 kms away from P, at the same time. On the way, however, the bus lost about 37.5 minutes while stopping at the ... is the speed of the jeep? a) 64 km/hr b) 72 km/hr c) 68 km/hr d) 56 km/hr

Last Answer : B Let speed of the jeep =x kmph Then, speed of the bus =(100+25)x/100 =125x/100 =5x/4 kmph Time taken by the jeep to travel from P to Q =225/x hours Time taken by the bus to travel from p to Q =225/(5x/4) + ... 225/x=900/5x+37.5/60 225/x=180/x+37.5/60 45/x =37.5/60 37.5x=45*60 X=72 km/hr

Description :  A train overtakes two girls walking along a railway track. The first girl walks at 9 km/hr. The other girl walks at 10.8 km/hr. The train needs 16.8 and 17 seconds respectively to overtake them. What is the speed of the ... in the same direction as the train? A) 25 m/s B) 45 m/s C) 30m/s D) 40m/s

Last Answer : ANSWER:B Explanation:  First girl speed = 9km/hr  = 9 * 5 / 18 m/s  = 5/2 m/s  = 2.5 m/s  second girl speed = 10.8 km/hr  = 10.8 * 5/18 m/s  = 54/18  = 3 m/s  Let the speed of the train ... x - 3) * 17  16.8x - 42 = 17x - 51  0.2x = 9  x = 45  Therefore the speed of the train is 45 m/s

Description : Jackson travels a distance of 100km in 5 hrs. How much faster in kilometer per hr, on an average, must he travel to make a journey in 5/3 hr less time? a) 5 km/hr b) 10km/hr c) 6 km/hr d) 8 km/hr

Last Answer : B Time required = (5 hrs – 5/3 hrs) =(5 hrs – 100 mints) = (5 hrs – 1hr 40 mints) = 3 hrs 20 mints = 3 1/3 hrs Required speed = (100*3/10) km/hr =30 km/hr Original speed = (100/5)km/hr = 20 km/hr Difference speed = required speed – original speed =(30-20) =10km/hr

Description : A train 200m in length, travels at 120 km/hr. In what time it will pass a boy who is walking at 12km an hour. a) against(opposite) it: b) in the same direction? A) 5.4,6.66 B) 7.2,5.2 C) 3.5,6 D) 12,16

Last Answer : ANSWER: A  Explanation: I) Speed of the train = 120 km/hr  Speed of the boy = 12 km/hr  Relative speed = (120 + 12) km/hr  Convert km/hr into m/s  132 km/hr = (132 * 5/ 18)m/s  = 36.66 m/s  Time = ... km/hr = (108 * 5 / 18)m/s  = 30 sec  Time = distance / speed  = 200 / 30  = 6.66 sec

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 : There is a bridge besides a river. Two friends Arun and varun started their journey from place L, moved to the garden located at another place M & then returned to place L. Arun moves by swimming at a speed of 30 ... 12km/hr, what will be the average speed of boat sailor? A) 36 B) 18 C) 24 D) 48 

Last Answer : ANSWER:B Explanation: As Arun swims both the ways at the speed of 30km/hr, the average speed of swimming is 30 km/hr Being a boat sailor, varun moves downstream at speed =24 +12=36km/hr and upstream at speed = 24-12= ... Upstream Speed])] = (36*12)/0.5(36+12) km/hr = 432/24 km/hr = 18 km/hr

Description : A girl is walking at a speed of 15 km/hr along a railway track. If she is 600 m ahead of the train which is 300 m long and runs at a speed of 180 km/hr in same direction, then what is the time required to pass a girl? A) 19.63sec B) 32sec C) 8.2sec D) 28.3sec

Last Answer : ANSWER:A Explanation:  Speed of a girl = 15 km/hr  speed of train = 180 km/hr By using the condition, The speed values of train and the moving object are subtracted if they are moving in same ... /45.83 = 19.63  Hence the time taken by the train to cross the girl is 19.63seconds

Description : Overall thermal efficiency of a lumpy coal fired suitably designed heating furnace, if operated & maintained properly may be about __________ percent. (A) 10-15 (B) 25-30 (C) 45-50 (D) 65-70

Last Answer : (B) 25-30

Description : Robert travels from his home to anna park at a distance of 125 miles in 11/4 hrs. He returns to home in 2 hrs 15 mints. His average speed is. a) 50 b) 40 c) 30 d) 20 

Last Answer : A Speed from home to annapark: (125*4/11)mph = (500/11)mph Speed from annapark to home: (125*4/9)mph = (500/9) mph Average speed = 2xy / (x+y) mph =[(2*500/11 *500/9) / (500/11+500/9)]mph =(500000/99) / ((4500+5500)/99) =(500000/99) / 10000 /99 =50mph

Description : P,Q & R are on a journey by scorpio. P drives during the 1st 2 hrs at an average speed of 60 km/hr. Q drives during the next 3 hrs at an average speed of 58 km/hr R drives for the next 4 hrs at an average speed of 62 ... exactly 5 hrs. Their main speed is. a) 60 2/9 b) 62 2/9 c) 60 4/8 d) 62 4 /8 

Last Answer : A Distance covered by P = 2*60 = 120 km Distance covered by Q = 3* 58 = 174 km Distance covered by R = 4*62 = 248 km Total distance = (120+174+248)km =542 km Total time taken = 2+3+4 = 9 hrs Mean speed = diatance/ time =(542 / 9)km/hr =60 2/9 km/hr

Description : Stopping distance of vehicles : When brakes are applied to a moving vehicle, the distance it travels before stopping is called stopping distance. It is an important factor for road safety and depends on ... the brake with the deceleration of 5m/s2. Find the stopping distance of the car -Science

Last Answer : Here u=72 km/hr = 72×10003600m/s=2072×10003600m/s=20 m/s , v=0 a= -5 m/s2 Now using the relation v2=u2+2asv2=u2+2as 0=(20)2+2×(−5)×s0=(20)2+2×(−5)×s s=40ms=40m

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 : What is the average speed of a skateboarder who travels 15 km in 1.5 hours?

Last Answer : I have know clue

Description : A train 125 m long passes a man, running at 5 kmph in the same direction in which the train is going, in 10 seconds. The speed of the train is: A.35 km/hr B.50 km/hr C.48 km/hr D.55 km/hr E.None of these

Last Answer : Answer – B (50 km/hr) Explanation – Let speed be S Relative speed = total lengths/time [ in this case man length is neglible compare to train so neglected] (S – 5) x 5/18 = 125 /10 S- 5 = (125/10)x(18/5) S-5 = 45 S=50 km/hr