SOLUTION: • One pipe can fill a tank in 5hrs less than another , together they fill the tank in 5hrs , how long will it take each to fill the tank?

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Question 667146: • One pipe can fill a tank in 5hrs less than another , together they fill the tank in 5hrs , how long will it take each to fill the tank?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
One pipe can fill a tank in 5hrs less than another , together they fill the tank in 5hrs , how long will it take each to fill the tank?
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let x=hours 1st pipe can fill the tank alone
1/x=its work rate
x-5=hours 2nd pipe can fill the tank alone
1/(x-5)=its work rate
1/5=work rate of both pipes working together filling the tank
..
sum of individual work rates=work rate working together
1/x+1/(x-5)=1/5
LCD:5x(x-5)
5x-25+5x=x^2-5x
x^2-15x+25=0
solve for x by following quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1, b=-15, c=25
ans:
x≈1.91 (reject, not reasonable)
x≈13.1
x-5≈9.1
1st pipe can fill the tank alone in 13.1 hrs
2nd pipe can fill the tank alone in 9.1 hrs