Question

A person who is 6ft tall walks away from a streetlight. When the person is 15 feet away from the light, the tip of his shadow is 5 feet in front of him. Find the height of the streetlight

Answer 1

We essentially have a ratio here:

`(shadow)/(actual)`

Since we know the ratio is going to stay constant at
`(5)/(6)`, we can use this to find the height of the lamp along with the information that the total distance from the lamp to the tip of his shadow is 20:

`(5)/(6)=(20)/(h)`

`5h=120`

`h=24`