Quiz Discussion

A plane left half an hour later than the scheduled time and in order to reach its destination 1500 kilometers away in time, it had to increase its speed by 33.33 percent over its usual speed. Find its increased speed.

• 1] 250 kmph
• 2] 500 kmph
• 3] 750 kmph
• 4] 1000 kmph
• 5] 1200 kmph

The speed of a motor-boat is that of the current of water as 36:5. The boat goes along with the current in 5 hours 10 minutes. It will come back in:

• 1] 5 hours 50 minutes
• 2] 6 hours
• 3] 6 hours 50 minutes
• 4] 12 hours 10 minutes

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

If two incorrect watches are set at 12:00 noon at correct time, when will both watches show the correct time for the first time given that the first watch gains 1 min in one hour and second watch looses 4 min in two hours.

• 1] 6 PM, 25 days later
• 2] 12 noon, 30 days later
• 3] 12 noon, 15 days later
• 4] 6 AM, 45 days later
• 5] None of these

When do the two hands of a clock of just after 3 pm make 30°angel between them?

• 1] 3:15:00
• 2] 3:10:54
• 3] 3:01:59
• 4] 3:5:20

A 6 × 6 grid is cut from an 8 × 8 chessboard. In how many ways can we put two identical coins, one on the black square and one on a white square on the grid, such that they are not placed in the same row or in the same column?

• 1] 216 ways
• 2] 324 ways
• 3] 144 ways
• 4] 108 ways

A racetrack is in the form of a right triangle. The longer of the legs of track is 2 km more than the shorter of the legs (both these legs being on a highway). The start and end points are also connected to each other through a side road. The escort vehicle for the race took the side road and rode with a speed of 30 km/h and then covered the two intervals along the highway during the same time with a speed of 42 km/h. find the length of the race track.

• 1] 14 km
• 2] 10 km
• 3] 24 km
• 4] 36 km
• 5] 30 km

Two boats A and B start towards each other from two places, 108 km apart. Speed of the boats A and B in still water are 12 km/h and 15 km/h respectively. If A proceeds down and B up the stream, they will meet after:

• 1] 4.5 hours
• 2] 4 hours
• 3] 5.4 hours
• 4] 6 hours

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 moving train crosses a man standing on a platform and the platform 300 metres long in 10 seconds and 25 seconds respectively. What will be the time taken by the train to cross a platform 200 metre long ?

• 1]

  \(16\frac{2}{3} \)seconds

• 2]

  18 seconds

• 3]

  20 seconds

• 4]

  22 seconds