First convert -5/6(b+1) to -5/6b-5/6 which looks like:
1/3b+2/3b-5/6b-5/6
second add 1/3b+2/3b=3/3b, convert to 6/6b so:
6/6b-5/6b-5/6
subtract 6/6b-5/6b = 1/6b so:
1/6b-5/6 is the answer
Five ice cream cones would cost 13.75 at the rate that each cone costs 2.75
If George completed 3/5 of work in 9 days, it means that he needs 3 days to finish 1/5th of the work.
The remaining part is 2/5 because 1-3/5=2/5. 2/5 is also 6/15
From this, how much did George do? in the first 3 days he did 1/5th and then one more day was left, during which he did 1/5/3=1/15th.
So he did in total 1/15+1/5=1/15+3/15=4/15.
this means that Paul did the rest of 6/15, so Paul did 6/15-4/15=2/15.
So we know that he does 2/15 in 4 days, which means that every two days he can do 1/15 of the work
so he would need 15 times 2 days to finish the work - 30 days!
(a+b+c)/2. this is your answer. if it had the numbers i would solve it fully, but it only has variables.