SSC CHSL 2022 PYQ — Question 59

The correct answer is option 4 i.e. 19.2 km/h.

Given:

Speed from A to B, x = 24 km/h

Speed from B to A, y = 16 km/h

Concept Used:

$Average\ speed = {2xy \over(x+y)}$   ...(i)

Explanation:

According to the given question,

Average speed = $2 × 24 × 16 \over (24 + 16)$    {using equation(i)}

⇒ Average Speed = $2 × 24 × 16 \over 40$

⇒ Average speed = 19.2

Hence the average speed of the whole journey is 19.2 km/h.