document.write( "Question 863009: Helping my child do her math and could use some help.\r
\n" ); document.write( "\n" ); document.write( "Twin brothers, person A and person B, can mow their grandparents lawn together in 42 minutes. Person A could mow the lawn by himself in 13 minutes less time than person B. How long does it take each person to mow the lawn by himself.\r
\n" ); document.write( "\n" ); document.write( "Many thanks in advance, \n" ); document.write( "

Algebra.Com's Answer #520131 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "Hi
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document.write( "The Set-Up concept is how much Lawn per minute:
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document.write( "    A  + B = together
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document.write( "   Multiplying thru by 42x(x-13) so as all denominators = 1
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document.write( "   42x + 42(x-13) = x(x-13)
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document.write( "   84x - 546 = x^2 - 13x
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document.write( "  x^2 -97x + 546 = 0
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document.write( "      x =  182/2 = 91min    |Note must be more than 42, root of 6 is Extraneous
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document.write( "B takes  
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document.write( "and..
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document.write( " 1/78 + 1/91 = 1/42 \n" );
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