[Classic]

I have done my research on how to try and solve this problem:

A student trtrated a solution containing 3.7066g of an unk. TRIPROTIC acid to the end point using 28.94 ml of 0.3021 M KOH solution.  What is the molar mass of the unk. acid? 

I think I am supposed to wrtie the 3 equations that come from a tripotic acid but I am lost from there? I could really use some guidance on how to solve this problem?

Thanks for any help,
Classic

[AWK]

Hint
you have 0.02894 x 0.3021 /3 moles of unknown acid