The document discusses finding the least common multiple (LCM) of numbers using prime factorizations. It provides examples of finding the LCM of various number pairs and groups by writing out their prime factorizations, identifying the largest common exponent for each prime factor, and multiplying the prime factors with those exponents. The document also provides tips for mentally calculating quotients by doubling numbers instead of dividing fractions.

1. lesson 27.notebook October 29, 2012
Lesson 27:
FYI...
*We can use Prime Factorization to find the Least Common
Multiple (LCM) of sets of numbers!
To find the LCM...
­Do the factor tree...write your answer with exponents
­Bring down EVERY base with the LARGEST exponent
­Multiply it out to find the LCM!
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2. lesson 27.notebook October 29, 2012
Examples (Lesson 27):
Find the Least Common Multiple (LCM) of each pair or group
of numbers.
A) 8 ­
10 ­
LCM ­
B) 4 ­
6 ­
10 ­
LCM ­
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3. lesson 27.notebook October 29, 2012
C) 24 ­
40 ­
LCM ­
D) 30 ­
75 ­
LCM ­
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4. lesson 27.notebook October 29, 2012
E) Instead of dividing 7 1/2 by 1 1/2, double each number
and mentally calculate the quotient.
Mentally calculate the following:
F) 24,000 400
G) $6.00 12
H) 140 5
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