Quiz Discussion

Two planes move along a circle of circumference 1.2 km with constant speeds. When they move in different directions, they meet every 15 seconds and when they move in the same direction, one plane overtakes the other every 60 seconds. Find the speed of the slower plane.

• 1] 0.04 km/s
• 2] 0.03 km/s
• 3] 0.05 km/s
• 4] 0.02 km/s
• 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

Two ports A and B are 300 km apart. Two ships leave A for B such that the second leaves 8 hours after the first. The ships arrive at B simultaneously. Find the time the slower ship spent on the trip if the speed of one of them is 10 km/h higher than that of the other.

• 1] 25 hours
• 2] 20 hours
• 3] 15 hours
• 4] 20 hours
• 5] 24 hours

The length of a train and that of a platform are equal. If with a speed of 90 km/hr the train crosses the platform in one minute, then the length of the train (in meters) is ?

• 1] 500 meters
• 2] 600 meters
• 3] 750 meters
• 4] 900 meters

Points 'A' and 'B' are 70 km apart on a highway and two cars start at the same time. If they travel in the same direction, they meet in 7 hours, but if they travel towards each other they meet in one hour. Find the speed of the two cars (in km/hr).

• 1] 20, 30
• 2] 40, 30
• 3] 30, 50
• 4] 20, 40

A truck covers a distance of 550 metres in 1 minute whereas a bus covers a distance of 33 kms in 45 minutes. The ratio of their speed is :

• 1] 4 : 3
• 2] 3 : 5
• 3] 3 : 4
• 4] 50 : 3

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

A boy is running at a speed of p kmph to cover a distance of 1 km. But, due to the slippery ground, his speed is reduced by q kmph (p > q). If he takes r hours to cover the distance, then:

• 1]

  \(\frac{1}{r} = p - q\)

• 2]

  r = p - q

• 3]

  \(\frac{1}{r} = p + q\)

• 4]

  r = p + r

Jane travelled \(\frac{4}{7}\) as many miles on foot as by water and \(\frac{2}{5}\) as many miles on horseback as by water. If she covered a total of 3036 miles, how many miles did she travel on foot?

• 1] 1540 miles
• 2] 880 miles
• 3] 756 miles
• 4] 616 miles

A and B start at the same time with speed of 40 km/hr. and 50 km/hr respectively. If in covering the journey A takes 15 min longer than B, the total distance of the journey is :

• 1] 40 km
• 2] 48 km
• 3] 50 km
• 4] 52 km