Question

A lighthouse casts a 128-ft shadow. A nearby lamppost that measures 5

feet casts an 8-foot shadow. What is the height of the light house, rounded
to the nearest foot? *

Answer 1

Answer: 80 feet

Explanation:

We can write these as fractions and do cross multiplication with the numerator being the height of the object while the denominator being the length of the shadow:

5 * 128 = 8x

640 = 8x

80 = x

Thus, the height of the lighthouse is 80 feet tall.