Quiz Discussion

A boy rides his bicycle 10 km at an average speed of 12 km/hr and again travels 12 km at an average speed of 10 km//hr. His average speed for the entire trip is approximately:

• 1] 10.4 km/hr
• 2] 10.8 km/hr
• 3] 11 km/hr
• 4] 12.2 km/hr

Two joggers left Delhi for Noida simultaneously. The first jogger stopped 42 min later when he was 1 km short of Noida and the other one stopped 52 min later when he was 2 km short of Noida. If the first jogger jogged as many kilometers as the second, and the second as kilometers as first, the first one would need 17 min less than the second. Find the distance between Delhi and Noida?

• 1] 5 km
• 2] 15 km
• 3] 25 km
• 4] 35 km
• 5] 24 km

The average speed of a bus is one-third of the speed of a train. The train covers 1125 km in 15 hours. How much distance will the bus cover in 36 minutes ?

• 1] 12 km
• 2] 18 km
• 3] 21 km
• 4] 75 km
• 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

Two boats, travelling at 5 km/h and 10 km/h, head directly towards each other. They begin at a distance of 20 km from each other. How far apart are they (in km) one minute before they collide?

• 1]

  \(\frac{{1}}{{12}}\)

• 2]

  \(\frac{{1}}{{6}}\)

• 3]

  \(\frac{{1}}{{4}}\)

• 4]

  \(\frac{{1}}{{3}}\)

• 5]

  None of these

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

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

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.

A man covers half of his journey at 6 km/h and the remaining half at 3 km/h. His average speed is

• 1] 9 km/h
• 2] 4.5 km/h
• 3] 4 km/h
• 4] 3 km/h

A car covers a distance from town 1 to town 2 at the speed of 56 km/hr and from town 2 to town 1 at the speed of 53 km/hr. What is the average speed of the car ?

• 1] 53.5 km/hr
• 2] 54 km/hr
• 3] 55 km/hr
• 4] 55.5 km/hr
• 5] None of these