Question

A car travels from point 'A' to point 'B' which are $160km$ apart in $3\text{hours}$. The car comes back to point 'A' in $2\text{hours}$. Calculate the average speed of the car.

• A. $0km{h}^{-1}$
• B. $8km{h}^{-1}$
• C. $16km{h}^{-1}$
• D. $64km{h}^{-1}$

Answer 1

The correct option is D $64km{h}^{-1}$

The car travels from 'A' to 'B' and returns to the point 'A'.
The total distance covered:
$d=160+160=320km$
Total time taken for the entire journey:
$t=3+2=5h$
Average speed:
$v_a^{\prime }=\frac{d}{t}=\frac{320}{5}=64{kmh}^{-1}$.