Question

If the light is coming from the same position, the length of a person's shadow is proportional to their height. Adam and Cara are standing side-by-side, facing their shadows. Adam is 159 centimeters tall and casts a shadow 105 centimeters in height. If Cara is 140 centimeters tall, how many centimeters will she need to walk forward for the tip of her shadow to be directly in line with Adam's?

Answer 1

Since the length of a person's shadow is proportional to their height, we can set up a proportion:

Adam's height / Adam's shadow length = Cara's height / Cara's shadow length

Plugging in the values we know, we get:

159 / 105 = 140 / x

Solving for x, we get:

x = 92.84 centimeters

So Cara will need to walk forward about 92.84 centimeters for the tip of her shadow to be directly in line with Adam's.