Question

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

Options

• 350 km 

• 420 km

• 384 km

• 400 km

Answer 1

384 km
Explanation:
Let the length of the journey = x

Then, `(x/2)/40+(x/2)/60=8`

⇒ `x/80+x/120=8`

⇒ 120x + 80x = 8 x 80 x 120

⇒ `x=(8xx80xx120)/200`

⇒ x = 384 km