SOLUTION: If two inlet pipes are both open, they can fill a pool in 1 hour and 30 minutes. One of the pipes can fill the pool by itself in 3 hours. How long would it take the other pipe to f

Algebra ->  Rate-of-work-word-problems -> SOLUTION: If two inlet pipes are both open, they can fill a pool in 1 hour and 30 minutes. One of the pipes can fill the pool by itself in 3 hours. How long would it take the other pipe to f      Log On


   

Question 809360: If two inlet pipes are both open, they can fill a pool in 1 hour and 30 minutes. One of the pipes can fill the pool by itself in 3 hours. How long would it take the other pipe to fill the pool by itself?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +t+ = time in hrs for the other pipe to
fill the pool by itself
--------------------
Add their rates of filling to get the rate filling together
( 1 pool filled ) / ( 3 hrs ) + ( 1 pool filled ) / ( t hrs ) = ( 1 pool filled ) / ( 1.5 hrs )
+1%2F3+%2B+1%2Ft+=++1%2F1.5+
Multiply both sides by +3t+
+t+%2B+3+=+2t+
+t+=+3+
The other pipe can fill the pool by itself in 3 hrs also
check:
+1%2F3+%2B+1%2F3+=+1%2F1.5+
+2%2F3+=+1%2F1.5+
Multiply both sides by +3+
+2+=+2+
OK