If a 30-foot silo casts a 20-foot shadow, what is the approximate measure from the tip of the shadow to the top of the silo? 650 feet
1,300 feet
13 feet
36 feet

9514 1404 393

  (d)  36 feet

Step-by-step explanation:

Use your sense of geometry.

The hypotenuse of a right triangle will never be less than the longest side, and will never be greater than 1.5 times the longest side*.

That means the only reasonable answer choices will be between 30 and 45 feet. There is only one such choice.

The measure is about 36 feet.

__

If you like, you can find a more exact value using the Pythagorean theorem. The distance d of interest is ...

  d^2 = 20^2 +30^2 = 1300

  d = √1300 = 10√13 ≈ 36.0555 ≈ 36 . . . feet

* The longest hypotenuse will be √2 ≈ 1.4142 times the longest right triangle leg when the two legs are equal length.