document.write( "Question 1197195: If Machine A can make a yo-yo every 5 minutes and Machine B can make a yo-yo every 10 minutes, how long wold it take them working together to make 20 yo-yo's? \n" ); document.write( "

Algebra.Com's Answer #830363 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "If Machine A makes a yo-yo every five minutes and Machine B takes ten minutes to make a yo-yo,
\n" ); document.write( "how many hours would it take them working together to make 20 yo−yos?
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document.write( "We assume that both machines started simultaneously.\r\n" );
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document.write( "Every 10 minutes, machine A produces 2 yo-yo; every 10 minutes machine B produces 1 yo-yo.\r\n" );
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document.write( "So, two machines produce 3 yo-yo every 10 minutes.\r\n" );
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document.write( "Divide 20 by 3 with a remainder: 20/3 = 6 + 2/3.\r\n" );
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document.write( "It tells you that in 6*10 = 60 minutes two machines will produce 6*3 = 18 yo-yos,\r\n" );
document.write( "which is still less than 20 yo-yous.\r\n" );
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document.write( "In the next 5 minutes, machine A will produce the 19-th yo-yo.\r\n" );
document.write( "In the next 5 minutes, machine A will produce the 20-th yo-yo, and machine B will complete the 21-th yo-yo.\r\n" );
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document.write( "Thus 20 yo-yo (and even 21 (!) yo-yo) will be completed 70 minutes after start moment.\r\n" );
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document.write( "70 minutes is the minimal time to wait to have 20 yo-yos completed.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved, with full explanations.\r
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\n" ); document.write( "\n" ); document.write( "The solution by @josgarithmetic is totally wrong, since it uses wrong idea that the production units \r
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\n" ); document.write( "\n" ); document.write( "go continuously in time, while the process is in discrete units.\r
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\n" ); document.write( "\n" ); document.write( "May god saves you from making such mistakes and from solving the problem by the method as @josgarithmetic does it.\r
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\n" ); document.write( "\n" ); document.write( "Would you solve it at the exam or at the Math competition in a way as @josgarithmetic does it, the lowest possible score is guaranteed to you.\r
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