document.write( "Question 1124682: John is one year less than three times as old as Ann. the sum of their ages is 79. What are their ages? \n" ); document.write( "

Algebra.Com's Answer #741009 by ikleyn(52790) $\"\"$ $\"About$

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document.write( "From the condition, you have these two equations\r\n" );
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document.write( "    J = 3A - 1     (1)     (\"John is one year less than three times as old as Ann.\")\r\n" );
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document.write( "    J + A = 79.    (2)     (It is clear without explanations)\r\n" );
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document.write( "From eq(1), substitute the expression for J into eq(2). You will get\r\n" );
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document.write( "    (3A-1) + A = 79\r\n" );
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document.write( "    4A = 79 + 1\r\n" );
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document.write( "    4A = 80  ====>  A = 80/4 = 20.\r\n" );
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document.write( "Answer.  Ann is 20 years old.  John is 79-20 = 59 years old.\r\n" );
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