Question

The picture shows a person taking a pinhole photograph of himself. Light entering the opening reflects his image on the wall, forming similar triangles. What is the height of the image to the nearest inch?

Answer 1

The height of the image is 18 inch.

Explanation:

It is given that the light entering the opening reflects his image on the wall, forming similar triangles.

We know that

1 ft =12 inch

The height of person is

`5\text{ ft }3\text{ in}=5* 12+3=63\text{ in}`

The distance of person form the wall is

`4\text{ ft }8\text{ in}=4* 12+8=56\text{ in}`

The distance of image form the wall is 16 in.

Let the height of image be x.

The corresponding sides of similar triangles are proportional.

`(x)/(16)=(63)/(56)`

`x=(63)/(56)* 16`

`x=18`

Therefore the height of the image is 18 inch.