document.write( "Question 1039627: Clara, Liz, and Maria are three sisters whose birthdays all fall on the same day. Clara is 2/3 as old as Liz; Maria is 1/6 as old as Clara; and Clara is in the sixth grade in a private school. If Liz is younger than 21, how old is she? \n" ); document.write( "

Algebra.Com's Answer #654385 by Edwin McCravy(20055) $\"\"$ $\"About$

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Clara is 2/3 as old as Liz;

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document.write( "Multiply both sides by 3 to clear the fraction\r\n" );
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document.write( "(1)

Maria is 1/6 as old as Clara

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document.write( "Multiply both sides by 6 to clear the fraction\r\n" );
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document.write( "(2)   \r\n" );
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document.write( "Use (2) to substitute 6M for C in (1):\r\n" );
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document.write( "(3)

Liz is younger than 21

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document.write( "Use (3) to substitute 9M for L\r\n" );
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document.write( "So Maria is either 1 or 2\r\n" );
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document.write( "If Maria were only 1, then, substituting\r\n" );
document.write( "M=1 in (2)   \r\n" );
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document.write( "But

Clara is in the sixth grade

So she can't be only 6.\r\n" );
document.write( "So Maria must be 2\r\n" );
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document.write( "(4)   M=2\r\n" );
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document.write( "substituting M=2 in (2)   \r\n" );
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document.write( "Normally one is only 11 in the sixth grade, but\r\n" );
document.write( "Clara could have failed a grade. So Maria is 2,\r\n" );
document.write( "and Clara is 12.

how old is she (Liz)?

Using (4) to substitute 2 for M in (3)\r\n" );
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document.write( "Liz is 18.\r\n" );
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document.write( "Edwin

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