Transcript Fractions and Decimals

Lesson 1
Greatest Common Factor
1.
Write three multiplication problems that equal 20.
2.
Find the value of 3 × 5.
3.
Find the value of 6 × 7.
Target:
Find the greatest common factor (GCF) of a set of numbers.
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Factors: Whole numbers that can be multiplied to get a
product.
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Prime Number: A whole number that has only two possible
factors (1 and itself).
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Composite Number: A number with more than two factors.
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Greatest Common Factor: The greatest factor that is
common to all the numbers.
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Prime Factorization: A composite number written as a
product of all its prime factors.
Determine if 12 is a prime or composite number.
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List the pairs of numbers that have a product of 12.
1 × 12 2 × 6 3 × 4
12 × 1 6 × 2 4 × 3
List each factor once.
1, 2, 3, 4, 6, 12
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There are more than two factors so 12 is composite.
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Two local teams went to soccer camp together. At the
camp the teams were asked to split into equal amounts
for cabin groups. The players did not want to room with
players from other teams. The camp directors want the
largest number possible in each cabin. How many players
will be in each cabin?
Team 1
Team 2
36 Players
30 Players
Write each number as a product of two factors until only
prime numbers remain.
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Write the prime
factorization of
each number and
highlight common
factors.
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Find the product of
the common factors.
3× 2 = 6
The GCF is 6.
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Reagan Middle School students were asked to sit in equal
rows for the assembly. There were 98 sixth graders, 84
seventh graders and 112 eighth graders. The teacher did not
want grade levels to sit together, but the rows were to be as
wide as possible. How many students should sit in each row?
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Factors of 98: 1, 2, 7, 14, 49, 98
Factors of 84: 1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84
Factors of 112: 1, 2, 4, 7, 8, 14, 16, 28, 56, 112
Highlight the common factors.
The GCF is 14.
Fourteen students should sit in each row.
1.
List the factors for each number.
2.
Highlight the common factors.
3.
Identify the GCF (greatest common factor).
1.
Find the GCF of 56 and 64.
2.
Gina wants to sell 49 chocolate chip cookies and 35
sugar cookies. She is going to sell them on plates
with equal amounts on each plate. Each plate needs
to hold the largest number of cookies without mixing
types of cookies. How many cookies should Gina put
on each plate?
What is a real life situation in which you would need to
find the greatest common factor?