using similar figures to solve problems

Question

the tree in your friend’s yard casts a shadow that is 27 feet long. your friend is 5 feet tall and casts a shadow that is 4.5 feet long. what is the height of the tree?

Answer 1

t/27 = 5/4.5

Cross multiply!

4.5t = 27(5)

4.5t = 135

t = 30 feet tall

Answer 2

4.5/5=27/x where x is the height of the tree. Then x=5•27/4.5 and x=30ft So tree is 30ft high.