Problema Solution
an inlet pipe can fill an empty swimming pool in 3 hours, and another inlet pipe can fill the pool in 4 hours. how long will it take both pipes to fill the pool?
Answer provided by our tutors
in 3 hours 1 work is done
in 1 hours 1/3 work is done
similiarly in 1 hour 1/4 work is done
so in 1 hour total work done is 1/3 +1/4 = 7/12 so they will take 12/7 hours ...