Answer:
I would say just take the big number and subtract the 41??...
I’m not sure but i think 66 hours because both pumps must fill half of the pool which would split the timing for each which would make pump 1 take 36 hours to fill half and pump two take 30 hours to fill the rest. when you add these hours it equals 66. i hope i helped :)
The answer would be 66.
6(-4 +15)
=
66