Quiz Discussion

Four people are running around a circular ground from a point on the circumference at 9.00 am. For one round, these four persons take respectively 40, 50, 60 and 30 minutes. At what time will they meet together again ?

• 1] 4.30 pm
• 2] 7.00 pm
• 3] 6.00 pm
• 4] 5.30 pm

Walking at the rate of 4 km an hour, a man cover a certain distance in 3 hours 45 minutes. If he covers the same distance on cycle, cycling at the rate of 16.5 km/hour, the time taken by him is :

• 1] 55.45 minutes
• 2] 54.55 minutes
• 3] 55.44 minutes
• 4] 45.55 minutes

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 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 guns are fired from the same place at an interval of 6 minutes. A person approaching the place observes that 5 minutes 52 seconds have elapsed between the hearings of the sound of the two guns. If the velocity of the sound is 330 m/sec, the man was approaching that place at what speed (in km/h)?

• 1] 24 kmph
• 2] 27 kmph
• 3] 30 kmph
• 4] 36 kmph

A car traveling with \(\frac{5}{7}\) of its actual speed covers 42 km in 1 hour 40 minute 48 seconds. Find the actual speed of the car.

• 1]

  \(17\frac{6}{7}\) km/hr

• 2]

  25 km/hr

• 3]

  30 km/hr

• 4]

  35 km/hr

Ravi and Ajay start simultaneously from a place A towards B 60 km apart. Ravi's speed is 4km/h less than that of Ajay. Ajay, after reaching B, turns back and meets Ravi at a places 12 km away from B. Ravi's speed is:

• 1] 12 km/h
• 2] 10 km/h
• 3] 8 km/h
• 4] 6 km/h

A 6 cm long cigarette burns up in 15 minutes if no puff is taken.For every puff, it burns three times as fast during the duration of the puff.If the cigarette burns itself in 13 minutes, then how many puffs has the smoker taken if the average puff lasted 3 seconds?

• 1] 17
• 2] 18
• 3] 20
• 4] 22
• 5] None of these

There are 8 equidistant points A, B, C, D, E, F, G and H in the clockwise direction on the periphery of a circle. In a time interval t, a person reaches from A to C with uniform motion while another person reaches the point E from the point B during the same time interval with uniform motion. Both the persons move in the same direction along the circumference of the circle and start at the same instant. How much time after the start, will the two persons meet each other ?

• 1] 4t
• 2] 7t
• 3] 9t
• 4] Never

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