Question

A plane flies 1.6 hours at 150 mph on a bearing of 10°. It then turns and flies 9.1 hours at the same speed on a

bearing of 100°. How far is the plane from its starting point?

Answer 1

9514 1404 393

Answer:

1386 miles

Explanation:

The plane flies ...

(150 mi/h)(1.6 h) = 240 mi

on its first leg. Then it flies ...

(150 mi/h)(9.1 h) = 1365 mi

on the second leg. The flight directions differ by 90°, so the distance from the starting point can be found using the Pythagorean theorem.

c² = 240² +1395² = 1920825

c = √1920825 ≈ 1385.94

The plane is about 1386 miles from its starting point.