9.28 days are taken to completely fill the pool
It is given that one pipe can fill the pool in 10 days
the other pipe can fill it in 25 days.
if no sewage is added, waste removal will empty the pool in 31 days.
The amount filled by pipe one in 1 day=1/10
The amount of pool filled by second pipe in 1 day=1/25
The waste removal pipe's work in 1 day= 1/31
Therefore, the work done together by all pipes in one day=1/10+1/25-1/31
= (775+310-250)/31*25*10=835/7750
Therefore, number of days taken to empty the pool= 7750/835=9.28 days
As half day cannot be counted, hence 9.28 days are taken to completely fill the pool
Disclaimer: The waste removal pipe has also been taken into consideration
For further reference:
brainly.com/question/13736913?referrer=searchResults
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