(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A lens has a focal length of 120 cm and a magnification of 4.0. How far apart are the object and the image?

2. Relevant equations

I used the thin lens equation 1/f = (1/di + 1/do)^-1 and M = -d image/d object

3. The attempt at a solution

I have been trying this by rearranging the thin lens equation...didnt work. Tried finding di and do given only magnification - cant do with only 1 known variable.

I dont think my approach is right at all. Any help will be appreciated.

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# Homework Help: Magnification and focal length

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