Question

A car completes a certain journey in 8 hours. It covers half the distance at 40 km/hr and the rest at 60 km/hr. The length of the journey is

• A. 350 km
• B. 420 km
• C. 384 km
• D. 400 km

Answer 1

Answer: (C)

384 km

Answer is C.
Let the total journey be x km.

$\frac{x}{2}\times \frac{1}{40}+\frac{x}{2}\times \frac{1}{60}=8$

Therefore, $\frac{x}{8}+\frac{x}{120}=8$

3x + 2x $=$ 1920

That is, 5x $=$ 1920, x$=$ 384 km.

Hence, The length of the journey is 384 km.