document.write( "Question 1109342: Rachel’s dad was 30 when she was born now he is 3x older than Rachel. How old is Rachel’s dad? \n" ); document.write( "

Algebra.Com's Answer #724326 by greenestamps(13203) $\"\"$ $\"About$

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\n" ); document.write( "The problem says her dad is \"3 times older than\" Rachel, meaning the difference in their ages is 3 times Rachel's age. (It does NOT mean that her dad is 3 times AS OLD AS her.)

\n" ); document.write( "So the difference in their ages is 3 times Rachel's age; but we know the difference in their ages is 30 years. So Rachel's age is 10; that makes her dad 40.

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\n" ); document.write( "Note: The answer by tutor stanbon -- that Rachel's dad is 45 years old -- is PROBABLY the answer the author of the problem wanted.

\n" ); document.write( "However, the right answer, using the grammatically correct interpretation of the given information, is that her dad is 40.

\n" ); document.write( "The problem is with the phrase saying that her dad is \"3x older\" than Rachel.

\n" ); document.write( "While everyday sloppy usage treats that the same as \"3x as old\", they mean different things.

\n" ); document.write( "For \"3x as old\", you obviously just multiply by 3.

\n" ); document.write( "But the grammatically correct interpretation of \"3x older\" is that her Dad is her age, plus 3 more times her age -- i.e., 4 times AS OLD. \n" ); document.write( "

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