Quiz Discussion

Two men start together to walk a certain distance, one at 4 km/hr and another at 3 km/hr. The former arrives half an hour before the latter. Find the distance :

• 1] 8 km
• 2] 7 km
• 3] 6 km
• 4] 9 km

Two rifles are fired from the same place at a difference of 11 minutes 45 seconds. But a man who is coming towards the place in a train hears the second sound after 11 minutes. Find the speed of train. (speed of sound = 330 m/s)

• 1] 72 kmph
• 2] 36 kmph
• 3] 81 kmph
• 4] 108 kmph
• 5] None of these

From two places, 60 km apart A and B start towards each other at the same time and meet each other after 6 hours. If A traveled with \(\frac{2}{3}\) of his usual speed and B traveled with double his speed they would have met after 5 hours. The speed of A is :

• 1] 4 km/hr
• 2] 6 km/hr
• 3] 10 km/hr
• 4] 12 km/hr

Running at \(\frac{5}{4}\) of his usual speed, an athlete improves his timing by 5 minutes. The time he usually takes to run the same distance is:

• 1] 30 min.
• 2] 28 min.
• 3] 25 min.
• 4] 23 min.

Two horses started simultaneously towards each other and meet each other 3 hr 20 mins later. How much time will it take the slower horse to cover the whole distance if the first arrived at the place of departure of the second 5 hours later than the second arrived at the point of departure of the first?

• 1] 10 hours
• 2] 5 hours
• 3] 15 hours
• 4] 6 hours
• 5] None of these

A train met with an accident 120 km from station A. It completed the remaining journey at \(\frac{5}{6}\) of its previous speed and reached 2 hours late at station B. Had the accident taken place 300 km further, it would have been only 1 hour late. What is the speed of the train?

• 1] 100 km/h
• 2] 12 km/h
• 3] 60 km/h
• 4] 50 km/h

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 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

Two boats go downstream from point X to Y. The faster boat covers the distance from X to Y, 1.5 times as fast as slower boat. It is known that for every hour slower boat lags behinds the faster boat by 8 km. however, if they go upstream, then the faster boat covers the distance from Y to X in half the time as the slower boat. Find the speed of the faster boat in still water?

• 1] 12 kmph
• 2] 20 kmph
• 3] 24 kmph
• 4] 25 kmph
• 5] None of these

A thief running at 8 km/hr is chased by a policeman whose speed is 10 km/hr. If the thief is 100 metres ahead of the policeman, then the time required for the policeman to catch the thief will be :

• 1] 2 minutes
• 2] 3 minutes
• 3] 6 minutes
• 4] 10 minutes