Quiz Discussion

A man covers half of his journey at 6 km/h and the remaining half at 3 km/h. His average speed is

• 1] 9 km/h
• 2] 4.5 km/h
• 3] 4 km/h
• 4] 3 km/h

A bus moving at a speed of 45 km/hr catches a truck 150 metres ahead going in the same direction in 30 seconds. The speed of the truck is :

• 1] 27 km/hr
• 2] 24 km/hr
• 3] 25 km/hr
• 4] 28 km/hr

A train can travel 50% faster than a car. Both start from point A at the same time and reach point B 75 kms away from A at the same time. On the way, however, the train lost about 12.5 minutes while stopping at the stations. The speed of the car is :

• 1] 100 kmph
• 2] 110 kmph
• 3] 120 kmph
• 4] 130 kmph

Two cars are moving with speed v1, v2 towards a crossing along two roads, If their distance from the crossing be 40 metres and 50 metres at an instant of time then they do not collide if their speeds are such that :

• 1]

  v1 : v2 =16 : 25

• 2]

  v1 : v2 e 4 : 5

• 3]

  v1 : v2 e 5 : 4

• 4]

  v1 : v2 e 25 : 16

A star is 8.1 × 1013 km away from the earth. Suppose light travels at the speed of 3.0 × 105 km per second. How long will it take the light from the star to reach the earth ?

• 1] 7.5 × 103 hours
• 2] 7.5 × 104 hours
• 3] 2.7 × 1010 seconds
• 4] 2.7 × 1011 seconds

Anna left for city A from city B at 5.20 am. She travelled at the speed of 80 km/hr for 2 hours 15 minutes. After that the speed was reduced to 60 km/hr. If the distance between two cities is 350 kms, at what time did Anna reach reach city A ?

• 1] 9.20 am
• 2] 9.25 am
• 3] 9.35 am
• 4] 10.05 am
• 5] None of these

The driver of an ambulance sees a school bus 40 m ahead of him after 20 seconds, the school bus is 60 meter behind. If the speed of the ambulance is 30 km/h, what is the speed of the school bus?

• 1] 10 kmph
• 2] 12 kmph
• 3] 15 kmph
• 4] 22 kmph

A man goes downstream with a boat to some destination and returns upstream to his original place in 5 hours. If the speed of the boat in still water and the stream are 10 kmph and 4 kmph respectively, the distance of the destination from the starting place is:

• 1] 16 km
• 2] 18 km
• 3] 21 km
• 4] 25 km

A is twice fast as B and B is thrice fast as C is. The journey covered by C in \(\frac{3}{2}\) hours will be covered by A is:

• 1] 15 minutes
• 2] 20 minutes
• 3] 30 minutes
• 4] 1 hour

A postman goes with a speed of 36 km/h what is the speed of postman in m/s?

• 1] 4.5 m/s
• 2] 6 m/s
• 3] 5 m/s
• 4] 10 m/s