$107.91
1) Gathering the data
Your 2 Day Pass: $76.50
Uncle's 2 Day Pass: x
2) We can write out the following equation with these pieces of information, considering that my 2-day pass is $31.41 cheaper than uncle's:
If my pass is cheaper than my uncle's in $31.41, to find out my uncle's pass I need to add up that difference.
3) So my uncle's pass is $107.91