Question

Bob is trying to see if his shadow is longer than Kevin’s. Kevin is 3 feet tall, and Bob is 2½ feet tall. Kevin’s shadow is 5 feet long. Help Bob find the length of his shadow

Answer 1

Given parameters:

Height of Kevin = 3ft

Height of Bob = 2.5ft

Hieght of Kevin's shadow = 5ft

Unknown:

Length of Bob's shadow = ?

We can simply set up simple ratio to solve this problem.

The ratio of Kevin's height to Bob's height is 3 : 2.5

The ratio of their shadow should also be 5: Bob's shadow height

Equating the two of them should give a fairly constant ratio;

`(3)/(2.5) = (5)/(Bob)`

3Bob = 5 x 2.5

Bob's shadow height =
`(5 x 2.5)/(3)` = 4.2ft

The height of Bob's shadow is 4.2ft.