Question

Sophie opened a picture of a tree on her cell phone screen and zoomed in 2.5 times. The new scale of the photograph became 1:168. What would be the scale if Sophie zoomed the image in 4 times?

Answer 1

1:105
The picture is 1 and the tree is 168 making the ratio 1:168. If you divided the 1 by the zoom which is 2.5 you get 0.4. Then you multiply 0.4 by 4 which is the new zoom. The final ratio is 1.6:168 and if you simplify, by dividing both sides by 1.6, you get 1:105