Question

An airplane has enough fuel for 3 hours of safe flying. On the trip out the pilot averages 200 mph flying against a headwind. On the trip back, the pilot averages 250 mph. How long a trip out can the pilot make?

Answer 1

`1 2/3` hours

Explanation:

Let airplane trips out for x hours. Hence trips in = 3 - x hours.

In x hours plane trips out = 200 x km as in 1 hours it goes 200 km.

Same way (3 - X) hours plane trips in 250 (3 - x) km as in 1 hours it goes 250 km.

Now, trips out = trips in [ means plane has to go some distances and returned back also the same distances within 3 hours.]

Thereby, 200 x = 250 (3 - x)

`rArr 200 x = 750 - 250 x`

`rArr 200 x + 250 x = 750`

`rArr 450 x = 750`

`rArr x = 750/450 = 5/3 = 1 2/3`

pilot makes `1 2/3` hours trip out