document.write( "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? \n" ); document.write( "
Algebra.Com's Answer #414820 by lwsshak3(11628)\"\" \"About 
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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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\n" ); document.write( "let x=hours 1st pipe can fill the tank alone
\n" ); document.write( "1/x=its work rate
\n" ); document.write( "x-5=hours 2nd pipe can fill the tank alone
\n" ); document.write( "1/(x-5)=its work rate
\n" ); document.write( "1/5=work rate of both pipes working together filling the tank
\n" ); document.write( "..
\n" ); document.write( "sum of individual work rates=work rate working together
\n" ); document.write( "1/x+1/(x-5)=1/5
\n" ); document.write( "LCD:5x(x-5)
\n" ); document.write( "5x-25+5x=x^2-5x
\n" ); document.write( "x^2-15x+25=0
\n" ); document.write( "solve for x by following quadratic formula:
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "a=1, b=-15, c=25
\n" ); document.write( "ans:
\n" ); document.write( "x≈1.91 (reject, not reasonable)
\n" ); document.write( "x≈13.1
\n" ); document.write( "x-5≈9.1
\n" ); document.write( "1st pipe can fill the tank alone in 13.1 hrs
\n" ); document.write( "2nd pipe can fill the tank alone in 9.1 hrs \n" ); document.write( "
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