document.write( "Question 1190088: Two boys can mow a lawn in 2 hours and 30 minutes. If they are joined by three other boys, how many hours will it take to mow the lawn?
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Algebra.Com's Answer #821650 by ikleyn(52788) $\"\"$ $\"About$

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\n" ); document.write( "A)1 hr B) 1 1/4 hrs C)1 1/2 hrs D)1 3/4 hrs E) 2 hrs
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document.write( "If two boys can mow a lawn in 2 hours and 30 minutes, it means that one boy, working alone, needs twice as much time,\r\n" );
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document.write( "which is 2 hours 30 minutes + 2 hours 30 minutes = 5 hours.\r\n" );
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document.write( "Hence, 5 boys working together, will complete the job in 5:5 = 1 hour.\r\n" );
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document.write( "The ANSWER is option (C).\r\n" );
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\n" ); document.write( "\n" ); document.write( " Alternative way to solve the problem is to use boy-minutes as a measure of the entire job, by analogy with men-days.\r
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document.write( "The entire job is 2*150 = 300 boy-minutes.\r\n" );
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document.write( "Hence, 5 boys will complete the job in  300:5 = 60 minutes = 1 hour.    ANSWER\r\n" );
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