Question 457756
one pipe can fill the pool in 3 hours. another pipe can fill the pool in 6 hours.
 The first pipe started filling at 9 am and the other pipe started filling at 10am.
 how long would it take to fill the pool?
:
Let t = time for both pipes to fill the pool
:
Let the completed job = 1 (A full pool)
:
Write a shared work equation, the 2nd pipe on 1 hr less
:
{{{t/3}}} + {{{(t-1)/6}}} = 1
multiply by 6
2t + t - 1 = 6
2t + t = 6 + 1
3t = 7
t = {{{7/3}}} hrs, 2 hrs 20 min from the time the 1st pipe was turned on