document.write( "Question 1151259: Liza is one year older than her sister. In four years Liza will be three times older than she is now. How old is Liza's sister now?
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Algebra.Com's Answer #772965 by ikleyn(52793) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "The original formulation in the post is DEFECTIVE, INACCURATE and potentially DANGEROUS.\r
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\n" ); document.write( "\n" ); document.write( "The correct, accurate and safe formulation is THIS :\r
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document.write( "      Liza is one year older than her sister. In four years Liza will be three times  as old as she is now. \r\n" );
document.write( "      How old is Liza's sister now?\r\n" );
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document.write( "Let x be the Lisa's age now.\r\n" );
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document.write( "Then from the condition\r\n" );
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document.write( "    x + 4 = 3x.     (In four years Liza will be three times as old as she is now).\r\n" );
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document.write( "From the equation,\r\n" );
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document.write( "    4 = 3x - x\r\n" );
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document.write( "    4 = 2x\r\n" );
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document.write( "    x = 4/2 = 2.\r\n" );
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document.write( "So, Lisa is 2 years old now.\r\n" );
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document.write( "ANSWER.  Lisa' sister is 2-1 = 1 year old now.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Here I want to explain you, why the original formulation in the post is DEFECTIVE, INACCURATE and potentially DANGEROUS.\r
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\n" ); document.write( "\n" ); document.write( "In English, in distinction from many other languages, the statement\r
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document.write( "    In four years Liza will be three times older than she is now.\r\n" );
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\n" ); document.write( "\n" ); document.write( "means \"In four years Liza will be FOUR times as old as she is now.\"\r
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\n" ); document.write( "\n" ); document.write( "In English, it is the only possible interpretation --- and there is NO any other interpretation.\r
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\n" ); document.write( "\n" ); document.write( "But it is, certainly and definitely, not that meaning the author of the problem was going to implement.\r
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\n" ); document.write( "\n" ); document.write( "Probably, the author of the problem is/was not familiar with this norm/form of English --- so, learn it from my post.\r
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\n" ); document.write( "\n" ); document.write( "The second message from me is that the \"solution\" and the setup in the post by @josgarithmetic is WRONG.\r
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\n" ); document.write( "\n" ); document.write( "So, you better IGNORE his post for your safety.\r
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