Quiz Discussion

A and B start from the same point and in the same direction at 7 am to walk around a rectangular field 400 m × 300 m. A and B walk at the rate of 3 km/hr and 2.5 km/hr respectively. How many times shall they cross each other if they continue to walk till 12.30 pm ?

• 1] Not even once
• 2] Once
• 3] Twice
• 4] Thrice

if a man increase his speed by 3km/hr,he reaches his home in 3/4th of his normal time. if he decreases his speed by 3km/h he reaches his home 2 hours late. what is the distance the man travel to reach his home​

• 1]

  32 km

• 2]

  34 km

• 3]

  36 km

• 4]

  38 km

An athlete runs 200 meters race in 24 seconds. His speed in km/h is

• 1] 20
• 2] 24
• 3] 28.5
• 4] 30

An ant moved for several seconds and covered 3 mm in the first second and 4 mm more in each successive second than its predecessor. If the ant had covered 1 mm in the first second and 8 mm more in each successive second, then the difference between the path it would cover during the same time and actual path would be more than 6 mm but less than 30 mm. find the time for which the ant moved (in seconds).

• 1] 5 s
• 2] 4 s
• 3] 6 s
• 4] 2 s
• 5] None of these

A dog start chasing to a cat 2 hour later. It takes 2 hours to dog to catch the cat. If the speed of the dog is 30 km/h. what is the speed of cat?

• 1] 10 km/h
• 2] 12 km/h
• 3] 15 km/h
• 4] 20 km/h

A man performs \(\frac{2}{15}\) of the total journey by rail, \(\frac{9}{20}\) by bus and the remaining 10 km, on the cycle. His total journey is :

• 1] 31.2 km
• 2] 38.4 km
• 3] 32.8 km
• 4] 24 km

A train running at \(\frac{7}{11}\) of its own speed reached a place in 22 hours. How much time could be saved if the train would have run at its own speed?

• 1] 7 hr
• 2] 8 hr
• 3] 14 hr
• 4] 16 hr

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 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

Two trains start simultaneously from two stations Howrah and Delhi, respectively towards each other on the same track. The distance between the two stations is 560 km and the speeds of trains are 30 kmph and 40 kmph.

• 1] 70 km
• 2] 560 km
• 3] 640 km
• 4] 650 km
• 5] None of these