Question

an object is kept at a distance of 60 CM in front of a convex lens it's real and inverted image is formed at a distance of 20 CM from the lence find the focal length of the lence​

Answer 1

Answer:

I'm sorry but I don't know how to solve the problem

Answer 2

Answer:

You can solve this problem by using lens formula

1/u - 1/v = 1/f