Greatest Common Factor (GCF)

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Show your work for each problem.

1.
What is the GCF of $6$ and $9$ ?
1. a)9
2. b)6
3. c)18
4. d)3
2.
What is the GCF of $8$ and $12$ ?
3.
Find the GCF of $15$ and $20$ by listing factors.
4.
Which pair of numbers is relatively prime (GCF = 1)?
1. a)6 and 9
2. b)8 and 15
3. c)10 and 25
4. d)12 and 18
5.
What is the GCF of $24$ and $36$ ?
6.
Find the GCF of $48$ and $60$ using prime factorization.
7.
Simplify $\frac{18}{24}$ using the GCF.
1. a) $\frac{9}{12}$
2. b) $\frac{6}{8}$
3. c) $\frac{3}{4}$
4. d) $\frac{2}{3}$
8.
A florist has 36 roses and 48 tulips. She wants to make identical bouquets with no flowers left over. What is the maximum number of bouquets she can make?
9.
What is the GCF of $42$ and $56$ ?
10.
What is GCF(50, 100)?
1. a)50
2. b)10
3. c)25
4. d)100
11.
Find the GCF of $18$ , $24$ , and $30$ .
12.
What is GCF(72, 96)?
13.
Simplify $\frac{84}{126}$ to lowest terms using the GCF.
14.
A carpenter has boards of 84 cm and 126 cm. She wants to cut both into pieces of the same length with no waste. What is the longest possible piece?
1. a)21 cm
2. b)7 cm
3. c)42 cm
4. d)14 cm
15.
Find the GCF of $10$ and $15$ .
16.
What is GCF(45, 75)?