MJ2 - Davidsen Middle School

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Transcript MJ2 - Davidsen Middle School

MJ2
Ch 5.7 Least Common Multiple
Bellwork
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1.
2.
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3.
4.
Write each percent as a decimal
42%
1.8%
Write each decimal as a percent
0.256
0.0525
Assignment Review
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Text p. 222 # 20 – 31
If you did not hand in this assignment,
please do so today.
Before we begin
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Please take out your notebook and get ready
to work….
Today we will look at the least common
multiple of 2 or more numbers….
Raise your hand if you can tell me what a
multiple is….
Objective
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Students will find the least common
multiple (LCM) of 2 or more numbers
Least Common Multiple
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A multiple is the product of a number and
any whole number.
Example:
– Multiples of 2 are 2, 4, 6, 8, 10…
When looking for the LCM you are looking
for the smallest multiple that 2 or more
numbers have in common
Finding the LCM
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There are several methods you can use to
find the LCM
– List the multiples
– Use a factor Tree
For today’s lesson we will focus on the cake
method….it is the most efficient method to
determine the LCM
So let’s look at an example
Example
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Find the LCM of 6 and 10
2
6, 10
3, 5
The LCM = 2 x 3 x 5 = 30
Let’s try another one…
Example
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Find the LCM of 10, 20 and 30
5
2
10, 20, 30
2, 4, 6
1, 2, 3
LCM = 5 x 2 x 1 x 2 x 3 = 60
Your Turn
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1.
2.
3.
In the notes section of your notebook
write the numbers and then find the LCM
3, 12
10, 12
4, 5
Assignment
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Text p. 226 # 8 – 19
Reminder
– This assignment is due tomorrow
– Write the numbers and use the cake method to
show how you got your answers
– Make sure that your heading has a name and
assignment number on it! (l letter grade
deduction each)