Concave mirror positioning help

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Homework Statement


A concave shaving mirror has a radius of curvature of 40 cm. It is positioned so that the (upright) image of a man's face is 3.30 times the size of the face. How far is the mirror from the face?


Homework Equations


M = Si/S 1/S + 1/Si = 2/R


The Attempt at a Solution


I have 2 equations with 2 unknowns. I isolated Si in the first one and substituted this expression into equation 2 to find S. I get an answer of 26.1cm.

The computer keeps telling me I'm wrong though. Could someone check my math or tell me if my equation setup is correct?
 
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oops never mind i got it... 13.94cm