Question

A 24 foot tree casts a shadow that is 9 feet long . At the same time a nearby building cats a shadow 45 feet long . how tall is the building?

Answer 1

I got `120"ft"`

Explanation:

Consider the diagram:

The angles `alpha` are the same so we can write for the two triangles (tree and building):
`h/l=H/L`
in numbers:
`24/9=H/45`
so that:
`H = 24/9*45=120"ft"`