1) 8 km/h 2) 9 km/h 3) 10 km/h 4) 12 km/h 5) None of these

Solution: (4).

Since 1 m/s = 18/5 km/h

Therefore 3 1/3 m/s = 10/3 m/s = 10/3 x 18/5 km/h

= 12 km/h

2. Two trains A and B travel from points X to Y and the ratio of the speeds of A to that of B is 2:7. Find

the ratio of time taken by A and B to reach from X to Y.

1) 2:5 2) 3:5 3) 3:8 4) 7:2 5) None of these

Solution: (4).

We know that speed is inversely proportional to time .

Given that,

( Speed of A ) : (Speed of B) = 2: 7

Therefore ( Time taken by A ) : ( Time taken by B)

= ½ : 1/7 = 7:2

3. A thief is noticed by a policeman from a distance of 200 m. The thief starts running and the

policeman, chases him . The thief and the policeman run at the rate of 10 km/h and 11 km/h ,

respectively. The distance between them after 6 min will be

1) 100 m 2) 180 m 3) 150 m 4) 125 m 5) None of these

Solution: (1).

Relative speed of policeman with respect to thief = ( 11 -10 ) = 1 km/h

Now, relative distance covered by policeman in 6 min

= Speed x Time = 1 x 6/60

= 1/10 km = 100m

= The distance between the policeman and thief after 6 min = ( 200 – 100) = 100m

4. John started from A to B and Vinod from B to A . If the distance between A and B is 125 km and

they meet at 75 km from A, what is the ratio of John’s speed to that of Vinod’s speed?

1) 2:3 2) 3:2 3) 4:3 4) 5:4 5) None of these

Solution: (2).

John’s speed : Vinod’s speed

= 75 : ( 125 – 75 )

= 75 : 50 = 3 : 2

5. A is twice as fast as B and B is thrice as fast as C. The journey covered by C in 56 min will be

covered by A in

1) 5 1/3 min 2) 2 1/3 min 3) 7 1/3 min 4) 9 1/3 min 5) None of these

Solution: ( 4).

Let time taken by A = y

Let speed of C = x

Then, speed of B = 3x

Therefore speed of A = 6x

Now, ratio of speeds of A and C

= Ratio of time taken by C and A

6x : x = 56 :y

= 6x /x

= 56/y

Therefore y = 56/6 = 9 2/6

9 1/3 min

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