For the sum 15 + 45
Factors of 15 = 1, 3, 5, 15
Factors of 45 = 1, 3, 5, 9, 15, 45
GCF = 15
Rewriting 15 + 45 as (15 × 1) + (15 × 3), we can take 15 out as the common factor, and we will get 15(1+3) = 15 × 4 = 60
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For the sum 9 + 27
Factors of 9 = 1, 3, 9
Factors of 27 = 1, 3, 9, 27
GCF = 9
Rewriting 9 + 27 as (9 × 1) + (9× 3) and taking the common factor, 9, out
We have 9(1+3) = 9 × 4 = 36
Writing 15 + 45 as a product of GCF ⇒ 15 ( 1 + 3 )
Writing 9 + 27 as a product of GCF ⇒ 3 ( 1 + 3 )