Calculating Biconvex Glass Lens Radius of Curvature for a +35-cm Focal Length

[Roof]

Question: A biconvex glass (n = 1.70) thin lens is to have a +35-cm focal length. If the radius of curvature of each surface is measured to be the same, what must it be? Give your answer in cm to two decimal places.

My answer:
I used this equation 1/f=(n-1)*(1/r1+1/r2), I got an answer 50cm. Am I right or I missing somthings? still doubt

 

[richyw]

I think this should be in the homework question section.

 

[Roof]

Thanks richyw

 

[jtbell]

Indeed, questions like this (solutions to specific exercises, whether they are actually assignments for a course or not) belong in one of the "Homework and Coursework Questions" forums. In this case, the "Introductory Physics" is the appropriate one.