Question 973120
It takes pipe A 2 hours longer than pipe B to fill up an empty pool. Using
both pipes, it takes 2.4 hours to fill up the same pool. How long does it take
each pipe, working alone to fill up the pool?
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let x=amt of time it takes pipe B to fill up the pool working alone
Its work rate=1/x
x+2=amt of time it takes pipe A to fill up the pool working alone
Its work rate=1/(x+2)
2.4=amt of time it takes pipe to fill up the pool using both pipes
Their work rate=1/2.4
{{{1/x+1/(x+2)=1/2.4}}}
lcd: 2.4x(x+2)
2.4(x+2)+2.4x=x(x+2)
2.4x+4.8+2.4x=x^2+2x
x^2-2.8x-4.8=0
(x-4)(x+1.2)=0
x=4
x+2=6
x=4
amt of time it takes pipe B to fill up the pool working alone=4 hrs
amt of time it takes pipe A to fill up the pool working alone=6 hrs