Quiz Discussion

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

To reach point B from point A at 4 pm, Sara will have to travel at an average speed of 18 kmph. She will reach point B at 3 pm if she travels at an average speed of 24 kmph. At what average speed should Sara travels to reach point B at 2 pm ?

• 1] 36 km/hr
• 2] 28 km/hr
• 3] 25 km/hr
• 4] 30 km/hr

A car traveled first 36 km at 6 km/h faster than the usual speed, but it returned the same distance at 6 km/h slower than usual speed. I the total time taken by car is 8 hours, for how many hours does it traveled at the faster speed ?

• 1] 4 hours
• 2] 3 hours
• 3] 2 hours
• 4] 1 hours

Two trains starting at the same time from two-stations 300 km apart and going in opposite directions, cross each other at a distance of 160 km from one of them. The ratio of their speeds is :

• 1] 7 : 9
• 2] 16 : 20
• 3] 8 : 7
• 4] 8 : 12

A ship, 40 kilometers from the shore, springs a leak which admits \(3\frac{3}{4}\) tonnes of water in 12 minutes. 60 tonnes would suffice to sink her, but the ship's pumps can throw out 12 tonnes of water in one hour. Find the average rate of sailing, so that she may reach the shore just as she begging to sink?

• 1]

  \(1\frac{1}{2}\) km/hr

• 2]

  \(2\frac{1}{2}\) km/hr

• 3]

  \(3\frac{1}{2}\) km/hr

• 4]

  \(4\frac{1}{2}\) km/hr

A man covers the journey from station A to station B at a uniform speed of 36 kmph and returns to A with a uniform speed of 45 kmph, his average speed for the whole journey is:

• 1] 40 kmph
• 2] 40.5 kmph
• 3] 41 kmph
• 4] 42 kmph

2 km 5 metres is equal to ?

• 1] 2.5 km
• 2] 2.005 km
• 3] 2.0005 km
• 4] 2.05 km

A train covers a distance of 10 km in 12 minutes. If its speed is decreased by 5 km/hr, the time taken by it to cover the same distance will be :

• 1] 10 minutes
• 2] 13 minutes 20 seconds
• 3] 13 minutes
• 4] 11 minutes 20 seconds

A man takes 50 minutes to cover a certain distance at a speed of 6 km/hr. If he walks with a speed of 10 km/hr, he covers the same distance in :

• 1] 10 min
• 2] 20 min
• 3] 30 min
• 4] 40 min

A thief is noticed by a policeman from a distance of 200 metres the thief starts running and the policeman chases him. The thief and the policeman run at the rate of 10 km/hr and 11 km/hr respectively. What is the distance between them after 6 minutes ?

• 1] 100 m
• 2] 190 m
• 3] 200 m
• 4] 150 m