document.write( "Question 471471: our mother is 3 times as old as my brother and i am 1/3rd times older than my brother. if 4 years ago i was as old as my brother today, what is the age of my mother? \n" ); document.write( "

Algebra.Com's Answer #323342 by Edwin McCravy(20056) $\"\"$ $\"About$

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Our mother is 3 times as old as my brother
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document.write( "M = 3B\r\n" );
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\n" ); document.write( "and i am 1/3rd times older than my brother.
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document.write( "You lost me there.  Are you 1/3 as old as your brother?\r\n" );
document.write( "If so you are YOUNGER, not OLDER, than your brother.\r\n" );
document.write( "Or are you your brother's age plus 1/3 of his age older?\r\n" );
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document.write( "If the first way, the equation is\r\n" );
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document.write( "I = B\r\n" );
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document.write( "If the second way then the equation is\r\n" );
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document.write( "I = B + B\r\n" );
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\n" ); document.write( "if 4 years ago i was as old as my brother today,
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document.write( "I - 4 = B\r\n" );
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document.write( "I'll try it both ways, but now I believe you meant the\r\n" );
document.write( "second way.  Otherwise this last sentence wouldn't make\r\n" );
document.write( "sense.\r\n" );
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document.write( "First way\r\n" );
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document.write( "I will assume you know how to solve a system of\r\n" );
document.write( "equations.  If you don't post again asking how\r\n" );
document.write( "to solve this system.\r\n" );
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document.write( "No that give B=-6, I = -2 and M = -18.\r\n" );
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document.write( "Second way:\r\n" );
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document.write( "Since ages can't be negative, you must have meant the \r\n" );
document.write( "other way:\r\n" );
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document.write( "Simplify the second equation:\r\n" );
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document.write( "Multiply through by 3\r\n" );
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document.write( "Solve that system and get B = 12, I = 16 and M = 36\r\n" );
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document.write( "So you are 16, your brother is 12, and your Mother is 36.\r\n" );
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document.write( "Edwin

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