Question 1

Suresh started cycling along the boundaries of a square field from corner point A. After half an hour, he reached the corner point C, diagonally opposite to A, if his speed was 8km/hr , what is the area of the field in square km.?

Accepted Answer

Length of two sides of square = 8 x 1/2 km. = 4 km. ∴ Area of the field = 2 x 2 sq. km = 4 sq. km.

Question 2

A man goes uphill with an average speed of 35 km/hr, and covers down with an average speed of 45 km/hr. The distance travelled in both the cases being the same , the average speed for the entire journey is?

Accepted Answer

Average speed = 2uv / (u + v) = ( 2 x 35 x 45) / (35 + 45) km/hr. = 39 3/8 km/hr

Question 3

If a boy takes as much time in running 10 m as a car takes in covering 25 m, the distance covered by the boy during the time the car covers 1 km, is?

Accepted Answer

Let distance covered by boy is Y. Then, 25 : 10 : : 1000 : Y ⇒ Y = (10 x 1000)/25 = 400 m

Question 4

The ratio between the rates of walking of A and B is 2:3 , if the time taken by B to cover a certain distance is 36 minutes, the time taken by A to cover that much distance is?

Accepted Answer

Ratio of speed = 2 : 3 Ratio of times taken for same distance = 1/2 : 1/3 From question 1/2 : 1/3 = t : 36 ⇒ (1/3) x t = (1/2) x 36 ∴ x = 54 min .

Question 5

A man, on tour travel first 160 km. at 64 km/hr. and the next 160 km. at 80 km/hr. The average speed for first 320 km. of the tour is?

Accepted Answer

Average speed = 2uv / ( u + v ) km/hr =(2 x 64 x 80) / (64 + 80) km/hr = (2 x 64 x 80) / 144 km/hr. = 71.11 km/hr

Question 6

By walking at 3/4 of his usual speed , a man reaches his office 20 minutes later than usual . this usual time is?

Accepted Answer

At 3/4 of the usual speed, the time taken is 4/3 of the usual time ∴ 4/3 of usual time - usual time = 20 min ⇒ 4x/3 - x = 20 ⇒ x/3 = 20 ∴ x = 60 min.

Question 7

A train is running with the speed of 45 km/hour. What is its speed in meter per second?

Accepted Answer

speed of a train in kilometer per hour =45 Speed in meter per second = ( 5/18 ) x Speed in kilometer per hour = 45 x 5/18 = 12.5 kmph

Question 8

If a motor car covers a distance of 250 m in 25 second, What is its speed in kilometer per hour?

Accepted Answer

Speed of the motor car in meter per second = 250 / 25 = 10 m/s Speed in km/hr = (18/5) x speed in m/s = 10 x (18 / 5) km/hour =36 km/hour.

Question 9

A man takes 4 h 20 min in walking to a certain place and riding back. If he walk on both sides he losses 1 h. The time he would take by riding both ways is?

Accepted Answer

W + R = 4 h 20 min W + W = 5 h 20 min ∴ R + R = 3 h 20 min

Question 10

A boat moves downstream at 1 km in 5 minutes and upstream at 1 km in 12 minutes.What is the speed of current?

Accepted Answer

Sd = 12 km/h Su = 5 km/h Speed of current = (12 - 5)/2 = 3.5 km/h

Question 11

A person goes to his office from his home at the speed of 4 km/h and return back at the speed of 6 km/h. Find the average speed of the person?

Accepted Answer

Average speed = 2ab/(a+b) = (2 x 4 x 6)/(4 + 6) = 48/10 = 4.8 km/h

Question 12

If a person travel 39 km at a speed of 26 km/h, another 39 km at a speed of 39 km/h and 39 km again at a speed of 52 km/h . Then find the average speed of entire journey

Accepted Answer

Average speed of entire journey = (39 + 39 + 39)/(39/26 + 39/39 +39/52) = 3/(1/26 + 1/39 +1/52) = 3/[(6 + 4 + 3)/156] = 3 x 156/13 = 36 km/h

Question 13

If speed of 3 1/ 3 m/s is converted to km/h, then it would be

Accepted Answer

∵ 1 m/s = 18/5 km/h ∴ 31/3 m/s = 10/3 m/s = (10/3) x (18/5) km/h = 12 km/h

Question 14

A car covers 300 km 15 h. Find the speed of the car?

Accepted Answer

We know that, speed = Distance / Time ∴ Required speed = 300/15 =20 km/h

Question 15

A car covers a distance of 690 km in 30 h. What is the average speed of the car?

Accepted Answer

Required speed = Distance/ Time = 690/30 = 23 km/h

Question 16

A bus is running with a uniform speed of 37 km/h. What distance will be covered by bus in 8 h?

Accepted Answer

We know that, Speed = Distance / Time ∴ Required distance = Speed x Time = 37 x 8 = 296 km

Question 17

A bus covers a distance of 400 km with a speed of 20 km/h. What time is taken by the bus to cover this distance?

Accepted Answer

We know that, speed = Distance / Time ∴ Required Time = Distance / Speed = 400/20 = 20 h

Question 18

The speed of a bus is 72 km/h. The distance Covered bye the bus in 5 s is

Accepted Answer

Given, speed of bus = 72 km/h = 72 x 5/18 = 20 m/s ∴ Distance travelled in 5 s = 5 x 20 = 100 m

Question 19

Ram and Shyam are moving in the directions opposite to each other. The Speeds of both persons are 10 km/h and 6 km/h, respectively. Find the speeds of Ram with respect of Shyam.

Accepted Answer

We know that for relative speed, the two speeds will be added, if the motions of the two objects are in opposite directions. ∴ Required speed = 10 + 6 = 16 km/h

Question 20

Two cars are moving in the same direction with their respective speeds of 9 km/h and 5 km/h. Find the relative speed of 1st car with respect of 2nd.

Accepted Answer

We know that for relative speed, the subtraction of speeds takes place, if the motions of the two objects are in the same direction. ∴ Required relative speed = 9 - 5 = 4 km/h

Time and Distance Questions