An inlet pipe can fill an empty pool in 3 hours. Another pipe can fill the same pool in 4 hours. How long will it take to fill the pool if both pipes are on?
time=1pool/(1pool/3 + 1pool/4)
Notice the rates add..1pool/4hrs + 1pool/3hrs.
time=12/7 hrs
so would this be 7 hrs or do i need to divide it out?
1 answer
You didn't work it out at all, just copied my outline. Work it out to get the answer, then you will answer your own question. This is a nice exercise in fractions.