GCF of 15 and 18?

2 Answers
Oct 30, 2017

3

Explanation:

# 15 = 3 xx5#
# 18 = 2 xx 3 xx3#

The Greatest Common Factor is 3

Oct 31, 2017

#GCF(15,18)=3#

Explanation:

list all the factors of each number and then pick out the common ones (marked in red)

Factors of#" "15:{color(red)(1),color(red)(3),5,15}#

Factors of#" "18:{color(red)(1),2,color(red)(3),6,9,18}#

Common factors#" "{1,3}#

#GCF(15,18)=3#