SOLUTION: two pipes are used to pump a cement mixture out of a truck. the pipes work at the same rate. when pipe A works alone it can empty the truck in 45 minutes. when both pipes are used

Question 1030837: two pipes are used to pump a cement mixture out of a truck. the pipes work at the same rate. when pipe A works alone it can empty the truck in 45 minutes. when both pipes are used together they empty the truck in 2/3 of the time that it takes pipe B to empty the truck it works alone. suppose pipe B takes x hours to empty the truck when it works alone. which equation can be used to find x?
Found 2 solutions by josmiceli, ikleyn:
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Rate of emptying for pipe A:
[ 1 truck emptied ] / [ 3/4 hrs ]
Rate of emptying for pipe B:
[ 1 truck emptied ] / [ x hrs ]
Rate of emptying for both pipes together:
[ 1 truck emptied ] / [ (2/3)*x hrs ]
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Add rates for pipes A and B to get
rate for both pipes together:

Multiply both sides by

----------------
check answer:

OK
Answer by ikleyn(52778) (Show Source): You can put this solution on YOUR website!
.
Your condition is wrong.

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