SOLUTION: one pipe can fill a cooling tank in 3 hours less that a second pipecan.if the two pipes together can fill seven-ninths of the tank in 4 hours ,how many hours would it take each pip
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-> SOLUTION: one pipe can fill a cooling tank in 3 hours less that a second pipecan.if the two pipes together can fill seven-ninths of the tank in 4 hours ,how many hours would it take each pip
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Question 548491: one pipe can fill a cooling tank in 3 hours less that a second pipecan.if the two pipes together can fill seven-ninths of the tank in 4 hours ,how many hours would it take each pipe alone to fill the tank Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! one pipe can fill a cooling tank in 3 hours less that a second pipe can.
if the two pipes together can fill seven-ninths of the tank in 4 hours,
how many hours would it take each pipe alone to fill the tank
:
Let p = one pipes filling time
then
(p+3) = another pipes filling time
:
Let a full tank = 1
: + =
Multiply by 9p(p+3), results
9(p+3)(4) + 9p(4) = 7p(p+3)
36p + 108 + 36p = 7p^2 + 21p
72p + 108 = 7p^2 + 21p
:
combine like terms on the right
0 = 7p^2 + 21p - 72p - 108
7p^2 - 51p - 108 = 0; a quadratic equation
You can use the quadratic equation here, but this will factor to:
(7p + 12)(p - 9) = 0
the positive solution is all we want here
p = 9 hrs time for one pipe alone
and
12 hrs for the other pipe alone
:
:
Let's check this out, using decimals + =
.444 + .333 = .777 which is very close to 7/9
