Snell's Law Question: Fish in a Fish Tank

[JamesEarl]

Homework Statement

A fish in a flat-sided aquarium sees a can of fish food on the counter. To the fish's eye, the can looks to be 49 cm outside the aquarium. What is the actual distance between the can and the aquarium? (You can ignore the thin glass wall of the aquarium.)

Homework Equations

s'=(n2/n1)s

The Attempt at a Solution

So at first I set n2=1.33 (the refraction index of water) and n1=1.00 (the refraction index of air). s= 49 cm. The answer of 65.2 that I got was wrong. I'm thinking maybe I have to switch up the variables, since it is from the perspective of the fish. Would it make sense to set n2= 1.00 and n2= 1.33? Would (49/1.33)=36.8 be the right answer? I have one more attempt and I don't want to risk it unless I'm 100% positive.

 

[kuruman]

Yes, it makes sense to switch indices of refraction in the formula for the apparent depth as seen from the rarer medium.