Question

A helicopter can fly at 90kph in still air. If it can fly 220 kilometers with a tailwind in the same time that it can fly 180 kilometers against a headwind, what is the speed of wind

Answer 1

Hey Dear,

◆ Answer -

Speed of wind = 9 kph

● Explaination -

Let vh and vw be speed of helicopter and wind.

Given that helicopter takes same time to travel 220 km with tailwind and 180 km with headwind.

s1 / (vh+vw) = s2 / (vh-vw)

We have, s1 = 220 km, s2 = 180 km and vh = 90 kph, so

220 / (90+vw) = 180 / (90-vw)

220×90 - 220vw = 90×180 + 180vw

(220-180)×90 = (180+220)vw

vw = 40×90 / 400

vw = 9 kph

Therefore, velocity of wind is 9 kph.

Thanks dear...