1. 25/120 2. 28/32 Find the GCF 3. 36 and 72 4. 56 and 88

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Warm­up
Write in simplest form:
1. 25/120
2. 28/32
Find the GCF
3. 36 and 72
4. 56 and 88
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Lesson
EQ: How do you use a cake to find the LCM?
Goal: 1.02
21st: Demonstrating ability to work effectivity with diverse
team.
Goals: 1.02
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Lesson 4.4
Least Common Multiple
Multiple: A multiple of a number is
the product of the number and any
nonzero whole number.
Example:
2: 2, 4, 6, 8, 10, 12, ...
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Common Multiple: A multiple that is
shared by two or more numbers.
Example:
2: 2, 4, 6, 8, 10, 12, ...
4: 4, 8, 12, 16, 20, ...
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Least Common Multiple: The least of
the common multiplies.
Example:
2: 2, 4, 6, 8, 10, 12, ...
4: 4, 8, 12, 16, 20, ...
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Example 1:
Find the least common multiple of 7 and 8.
The LCM of 7 and 8 is 56.
LCM 1x 7 x 8 = 56
GCF 1
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Example 2:
Find the least common multiple of 12 and 16.
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Example 3:
Find the least common multiple of 36 and 72.
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Example 4:
Find the least common multiple of 24 and 30.
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Example 5:
Find the least common multiple of 84 and 360.
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Example 6:
Find the least common multiple of 2, 6, and 14.
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Using the LCM
David and James are running laps on a quarter mile
track. it takes James 3 minutes and David 4
minutes to run once around the track. They both
start running from the starting line at the same
time. When will they both be at the starting line
again?
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Discussion Questions
How do we use cake to find the LCM?
How do we use cake to find the GCF?
How do we use cake to find the Equivalent Fraction?
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Quick Review!
True or False!
1. The GCF of 14 and 21 is 7. Prove!
2. The LCM of 25 and 70 is 300. Prove!
3. The simplest form of 48/72 is 24/ 36. Prove!
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Quiz 2: GCF, Equivalent Fractions, LCM!
Write out each problem!!! (Make sure you write out the letter so we can click it in later!)
1. Find the GCF of 24 and 63
A. 5 B. 3 C. 504 D. 78
2. Find the LCM of 49 and 56
A. 45 B. 67 C. 392 D. 7
3. Write the fraction in simplest form: 32
72
A. 4/9 B. 2/8 C. 16/36 D. 12/47
4. Write the fraction in simplest form: 28
48
A. 14/24 B. 8/48 C. 7/12 D. 7/48
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Homework tonight! Will be based off how you did on the
quiz! If you made a 100, then no homework! If you made
below that.. fix your mistake on the quiz!
I will check and give you extra points on the quiz grade!
http://e­learningforkids.org/Courses/EN/M1105/index.html
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