Quiz Discussion

A train passes two bridges of length 800 m and 400 m in 100 seconds and 60 seconds respectively. The length of the train is:

• 1] 80m
• 2] 90m
• 3] 200m
• 4] 150m

Two trains start from the same point simultaneously and in the same direction. The first train travels at 40 km /h, and the speed of the second train is 25% more than the speed of first train. Thirty minutes later, a third train starts from same point and in the same direction. It over takes the second train 90 minutes later than it overtook the first train. What is the speed of the third train?

• 1] 20 km/h
• 2] 40 km/h
• 3] 60 km/h
• 4] 50 km/h
• 5] 80 km/h

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

Two trains start from P and Q respectively and travel towards each other at a speed of 50 km/hr and 40 km/hr respectively. By the time they meet the first train has travelled 100 km more than second. The distance between P and Q is:

• 1]

  500 km

• 2]

  630 km

• 3]

  660 km

• 4]

  900 km

In a 1-kilometre race, A can beat B by 30 meters, while in a 500-meter race B can beat C by 25 meters. By how many meters will A beats C in a 100-meter race?

• 1] 7.85
• 2] 7.25
• 3] 7.15
• 4] 7.03

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

The average speed of a train in the onward journey is 25% more than that in the return journey. The train halts for one hour on reaching the destination. The total time taken for the complete to and fro journey is 17 hours, covering a distance of 800 km. The speed of the train in the onward journey is :

• 1] 45 km/hr
• 2] 47.5 km/hr
• 3] 52 km/hr
• 4] 56.25 km/hr

A train can travel 50% faster than a car. Both start from point A at the same time and reach point B 75 kms away from A at the same time. On the way, however, the train lost about 12.5 minutes while stopping at the stations. The speed of the car is :

• 1] 100 kmph
• 2] 110 kmph
• 3] 120 kmph
• 4] 130 kmph

A car goes 10 meters in a second. Find its speed in km/hour.

• 1] 40 km/hr
• 2] 32 km/hr
• 3] 48 km/hr
• 4] 36 km/hr

A person can row a boat d km upstream and the same distance downstream in 5 hours 15 minutes. Also, he can row the boat 2d km upstream in 7 hours. How long will it take to row the same distance 2d km downstream?

• 1]

  \(\frac{{3}}{{2}}\) hours

• 2]

  7 hours

• 3]

  \(\frac{{29}}{{4}}\) hours

• 4]

  \(\frac{{7}}{{2}}\) hours