![\bf \textit{sum of all interior angles in a polygon}\\\\ S=180(n-2)~~ \begin{cases} n=\textit{number of sides}\\[-0.5em] \hrulefill\\ n=8 \end{cases}\implies S=180(8-2) \\\\\\ S=180(6)\implies S=1080](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Bsum%20of%20all%20interior%20angles%20in%20a%20polygon%7D%5C%5C%5C%5C%20S%3D180%28n-2%29~~%20%5Cbegin%7Bcases%7D%20n%3D%5Ctextit%7Bnumber%20of%20sides%7D%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20n%3D8%20%5Cend%7Bcases%7D%5Cimplies%20S%3D180%288-2%29%20%5C%5C%5C%5C%5C%5C%20S%3D180%286%29%5Cimplies%20S%3D1080)
now, we know 7 of those angles are already 835°, so the last one must be 1080 - 835 = 245°.
72 I think it is I believe
The way your question is worded, the probability is zero. One ace is not two aces.
He sold 66 wrapping paper because all you want to do is divide
3x+3=9
x=2
that way the answer is 9