Apparent Height in a Swimming Pool

[rmcgovern]

Homework Statement

A person swimming 0.95 m below the surface of the water in a swimming pool looks at the diving board that is directly overhead and sees the image of the board that is formed by refraction at the surface of the water. This image is a height of 6.00 m above the swimmer. What is the actual height of the diving board above the surface of the water?

Homework Equations

(na/s)+(nb/s')=0

The Attempt at a Solution

Rearranging the equation, I found s'=(nb*s)/-na. Plugging in nb=1.00, s=6.00m, and na=1.33, I found s'=-4.51, adding the depth of the swimmer, my final solution was -3.56m. This however is not correct. I also tried solving for s (which was actually my first attempt, although masteringphysics says the variable to solve for is s') to no avail. Any suggestions on where I may have gone wrong?

 

[rl.bhat]

s is not the image distance from the surface of the water. 6.0 m is the sum of the image distance and the depth of the swimmer.

 

[rmcgovern]

ah, thank you for your help