document.write( "Question 386500: a mechanic and his helper can repair a car in 7 hours. the helper takes twice as long as the mechanic. how long would it take the helper to make the repair working alone? \n" ); document.write( "

Algebra.Com's Answer #273241 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "Let x and 2x represent the solo times for the mechanic and helper respectivly
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document.write( "Question States:  Per hour being Equalizer
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document.write( " 1/x + 1/2x = 1/7 Mulitplying each term by 14x so as all denominators = 1
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document.write( " 14 + 7 = 2x
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document.write( "    21 = 2x
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document.write( "     x = 21/2 = 10.5hrs, mechanics solo time, the helper's 21hr   (2*10.5)\r
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document.write( "CHECKING our Answer
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document.write( "  1/10.5 + 1/21 = .1429 hr = 1/7 \n" );
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