the floodlight is 6.1m tall. Jonny's height is unknown,though his shadow is 2m long when he stands 3m from the base of a floodlight.

What is the height of jonny?

H = Height

3 m + 2 m = 5 m

Proportion :

H / 2 = 6.1 / 5 Multiply both sides by 2

H = 6.1 * 2 / 5 = 12.2 / 5 = 2.44 m