Page 71 - Math Course 1 (Book 1)

LCM (Least Common Multiple)

Your Turn!

Find the LCM. The LCM of Monomials

Find the LCM of 144 and 96. Find the LCM of 18ab³ and 24a²b.
A. 2 A. 6ab
B. 144 B. 9a²b³
C. 288 C. 72a²b³

D. 13,824 D. 432a³b4

Answer Answer

MO. 2 - L3b
LCM = 2³ 5 or 40 Multiply
Finding the LCM
of Fractions 7 13
Answer The LCM of and is 40.
20
8
Vocabulary A-Z
Let us learn some vocabulary
Compare Fractions

Example
Least Common Denominator (LCD)
7 3
The least common denominator (LCD) of two or Replace • with <, >, or = to make a true
15
7
more fractions is the LCM of the denominators. statement.
The LCD of the fractions is 3 • 5 • 7 or 105.
5 11
The LCD of and is 63. Rewrite the fractions using the LCD and then
9 21
compare the numerators.

7 = 7 7 = 49 Multiply the fraction by 7
Let’s Begin 15 3 5 7 105 to make the denominator 7

105.
3 3 3 5 45 Multiply the fraction by
Find the LCD 7 = 7 3 5 = 105 3 5
to make the
3 5
Example denominator 105.

49
7 13 Answer Since > 45 , then 7 > 3
Find the LCD of and 150 150 15 7
8 20
8 = 2³ Write the prime factorization of 8
and 20.
20 = 2² 5 Highlight the greatest power of
each prime factor.

63