Physics 100 help?

Question

A student has built a 0.20 m long pinhole camera for a science fair project. She wants to photograph the Washington Monument, which is 167 m tall, and to have the image on the film be 0.05 m high. How far should she stand from the Washington Monument?

Answer 1

Distance from pinhole to camera back ÷ Size of image on camera back = Distance from object to pinhole ÷ Size of object.