Question

An airplane is at height of `10000` feet. At what angle (rounded to whole degree), it must descend if the airport is `50` miles away?

Answer 1

Airplane must descend at `2^@`.

Explanation:

As one mile is `1760` yards and each yard `3` feet, we have `1760xx3=5280` feet in a mile and

airport is `5280xx50=264000` feet away.

Hence tangent (equal to opposite side divided by adjacent side) of angle formed is `tanalpha=10000/264000=0.03788`

and looking at tables (or scientific calculator) angle `alpha=2.17^@`, which rounded to degrees is `2^@`.