<PRE><B>Question 310086</B>
7/9 - 7/12 =
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You have to get a common denominator.
The product always works, = 9*12 = 108
7/9 - 7/12 = 84/108 - 63/108 = 21/108
21/108 = 7/36
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You can waste time finding the LCD, Least Common Denominator, or just use the product.
It might mean reducing the result, but that&#39;s easy and never takes more time than finding the LCD.

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