Homework Help: elementary

Posted by Mary on Saturday, October 31, 2009 at 5:38pm.

Think of a number.
Add 7.
Double the result.
Subtract 8.
Double the result.
Add 12.
Divide by 4.
Subtract 6.
Your answer will be the original number. Explain how this trick works.

elementary math - Ms. Sue, Saturday, October 31, 2009 at 5:52pm
Your subject is math.
elementary - Reiny, Saturday, October 31, 2009 at 6:06pm
Think of a number.... x
Add 7.... x+7
Double the result..... 2x+14
Subtract 8....2x+6
Double the result.... 4x + 12
Add 12. 4x + 24
Divide by 4.... x + 6
Subtract 6.... x

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