Greatest Common Factor GCF

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Greatest Common Factor GCF
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A common factor is a whole number that is a
factor of two or more nonzero whole numbers.
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The GREATEST COMMON FACTOR (GCF) can be found two
ways.
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1. Listing factors of two numbers and finding
the largest one they have in common.2. Prime
factorization.
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List the factors of 60
1,2,3,4,5,6,10,12,15,20,30,60
List the factors of 96
1,2,3,4,6,8,12,16,24,32,48,96 find the common
factors
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List the factors of 601,2,3,4,5,6,10,12,15,20,3
0,60List the factors of 961,2,3,4,6,8,12,16,24
,32,48,96find the largest factor 12
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or do prime factorization. Circle all the
primes the 2 numbers have in common and multiply
one set of them to get your GCF.
96
60
48
2
2
30
24
2
15
2
12
2
3
5
6
2
2 x 2 x 3 12
2
3
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Finding GCF By Making a List
Find the GCF of 48 and 24 Factors of 48 1, 2,
3, 4, 6, 8, 12, 16, 24, 48 Factors of 24 1, 2,
3, 4, 6, 8, 12, 24
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Find GCF Through Prime Factorization
48 24 12 4 12
2 3 4 2 2 6 2
2 2 3 2 483 x 2 x 2 x 2 x 2
243 x 2 x 2 x 2 GCF 3 x 23 3
x 8 24, so 24 is the GCF