<PRE><B>Question 311053</B>
for instance 4/63+1/45
i can find GCF eventually just guessing, and same with simplifying answer of 27/315 to 3/35, but i do it by picking factors and narrowing it down until i find one that works. how can i find GCF faster and simplify it faster? 
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You can factor the terms:
63 = 3*3*7
45 = 3*3*5
Then pick out all factors that are not common (5 &amp; 7 here) and include enough of the ones that are, 2 3&#39;s in this case.
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Finding the GCF and the LCD are greatly over-rated, imo.


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