Question

In a 4.0-kilometer race, a runner completes the first kilometer in 5.9 minutes, the second kilometer in 6.2 minutes, the third kilometer in 6.3 minutes, and the final kilometer in 6.0 minutes. The average speed of the runner for the race is approximately
A) 0.16 km/min B) 0.33 km/min

C) 12 km/min D) 24 km/min

Answer 1

As per the question the total distance is given as 4 km.

We are asked to calculate the average speed.

The time taken by the body to travel each kilometre are 5.9 min,6.2 min.,6.3min. and 6 min. respectively.

The average speed of a body is defined as the ratio of total distance travelled by the body to the total time.

Mathematically the average speed is written as _

V= Total distance/Total time

i.e V = S/T

Where S is the total distance travelled and T is the total time

Here total distance (S)= 4 km

The total time T= (5.9+6.2 +6.3+ 6.0 )minutes

=24.4 min.

Hence average speed V = 4 km/24.4 min

= 0.16 km/min.

Hence the correct option is A .