How do you find the LCM of 7 and 9?

2 Answers
Dec 15, 2016

Answer:

63

Explanation:

Since the only number that #7# and #9# go into evenly is #63# we must consider this simple step:

#7*9=63#

A least common multiple is the smallest unit that both numbers can evenly be divided by. Since you can evenly divide #63# by both #7# and #9# the following is true:

#63# is the least common multiple of #7# and #9#.

Answer: 63

Aug 29, 2017

Answer:

#LCM = 7 xx9 = 63#

Explanation:

#7 and 9# have no common factor (apart from #1#).

Therefore the #LCM# must contain the whole #7# and the whole #9#.

#LCM = 7 xx9 = 63#

This is clear if we write #7 and 9# as the product of the prime factors:

#" "7 = 7#
#ul(" "9= " "3xx3)#

#LCM = 7 xx 3xx3 =63#