Here is the answer- 297. I hope this helps! I solved this by changing the fractions so that they had the same denominators.
To find the mean you add up all the numbers then divide the sum by how many numbers there are :
8+16+12+11+8=55
there are 5 numbers in the equation so you divide 55 by 5 :
55÷5= 11
the mean is 11
hope this helped
It's not clear what your series is, so I'm going to take a wild guess on what it is you mean:


For the sum to be absolute convergent, the sum of the absolute value of the summand must converge, so you are really examining the convergence of

This is easily checked with the ratio test:


Since

converges by the ratio test, the series

converges absolutely.
If you do 7-5 then you get 2. You can check by adding 2+5 to get 7. You do this because this is how you check your work .