# Find the GCF of 2 Numbers: Worksheets, Online Test and Calculators

Find the gcf of 2 numbers worksheets, solved worksheet problems or exercises with step-by-step work, formative assessment as online test, calculator and more learning resources to learn, practice, assess and master the basic math skills of divisors and factors.

## Find the GCF of 2 Numbers

Name
Date

1
Find the GCF of 5 and 10
2
Find the GCF of 6 and 15
3
Find the GCF of 10 and 8
4
Find the GCF of 12 and 20
5
Find the GCF of 14 and 21
6
Find the GCF of 9 and 12
7
Find the GCF of 16 and 20
8
Find the GCF of 30 and 45
9
Find the GCF of 24 and 30
10
Find the GCF of 15 and 9
11
Find the GCF of 18 and 27
12
Find the GCF of 8 and 12
13
Find the GCF of 9 and 12
14
Find the GCF of 6 and 8
15
Find the GCF of 8 and 10
16
Find the GCF of 12 and 15
17
Find the GCF of 12 and 18
18
Find the GCF of 12 and 16
19
Find the GCF of 6 and 9
20
Find the GCF of 24 and 36

Solved Worksheet Problems
1
Find the GCF of 5 and 10
5 is the GCF of 5 and 10
Factors of 5
 5 5 1
Factors of 10
 2 10 5 5 1

Factors of 5 = 5
Factors of 10 = 2 x 5
Multiply all the common factors of 5 and 10.
5 = 5
GCF(5, 10) = 5
2
Find the GCF of 6 and 15
3 is the GCF of 6 and 15
Factors of 6
 2 6 3 3 1
Factors of 15
 3 15 5 5 1

Factors of 6 = 2 x 3
Factors of 15 = 3 x 5
Multiply all the common factors of 6 and 15.
3 = 3
GCF(6, 15) = 3
3
Find the GCF of 10 and 8
2 is the GCF of 10 and 8
Factors of 10
 2 10 5 5 1
Factors of 8
 2 8 2 4 2 2 1

Factors of 10 = 2 x 5
Factors of 8 = 2 x 2 x 2
Multiply all the common factors of 10 and 8.
2 = 2
GCF(10, 8) = 2
4
Find the GCF of 12 and 20
4 is the GCF of 12 and 20
Factors of 12
 2 12 2 6 3 3 1
Factors of 20
 2 20 2 10 5 5 1

Factors of 12 = 2 x 2 x 3
Factors of 20 = 2 x 2 x 5
Multiply all the common factors of 12 and 20.
2 x 2 = 4
GCF(12, 20) = 4
5
Find the GCF of 14 and 21
7 is the GCF of 14 and 21
Factors of 14
 2 14 7 7 1
Factors of 21
 3 21 7 7 1

Factors of 14 = 2 x 7
Factors of 21 = 3 x 7
Multiply all the common factors of 14 and 21.
7 = 7
GCF(14, 21) = 7
6
Find the GCF of 9 and 12
3 is the GCF of 9 and 12
Factors of 9
 3 9 3 3 1
Factors of 12
 2 12 2 6 3 3 1

Factors of 9 = 3 x 3
Factors of 12 = 2 x 2 x 3
Multiply all the common factors of 9 and 12.
3 = 3
GCF(9, 12) = 3
7
Find the GCF of 16 and 20
4 is the GCF of 16 and 20
Factors of 16
 2 16 2 8 2 4 2 2 1
Factors of 20
 2 20 2 10 5 5 1

Factors of 16 = 2 x 2 x 2 x 2
Factors of 20 = 2 x 2 x 5
Multiply all the common factors of 16 and 20.
2 x 2 = 4
GCF(16, 20) = 4
8
Find the GCF of 30 and 45
15 is the GCF of 30 and 45
Factors of 30
 2 30 3 15 5 5 1
Factors of 45
 3 45 3 15 5 5 1

Factors of 30 = 2 x 3 x 5
Factors of 45 = 3 x 3 x 5
Multiply all the common factors of 30 and 45.
3 x 5 = 15
GCF(30, 45) = 15
9
Find the GCF of 24 and 30
6 is the GCF of 24 and 30
Factors of 24
 2 24 2 12 2 6 3 3 1
Factors of 30
 2 30 3 15 5 5 1

Factors of 24 = 2 x 2 x 2 x 3
Factors of 30 = 2 x 3 x 5
Multiply all the common factors of 24 and 30.
2 x 3 = 6
GCF(24, 30) = 6
10
Find the GCF of 15 and 9
3 is the GCF of 15 and 9
Factors of 15
 3 15 5 5 1
Factors of 9
 3 9 3 3 1

Factors of 15 = 3 x 5
Factors of 9 = 3 x 3
Multiply all the common factors of 15 and 9.
3 = 3
GCF(15, 9) = 3
11
Find the GCF of 18 and 27
9 is the GCF of 18 and 27
Factors of 18
 2 18 3 9 3 3 1
Factors of 27
 3 27 3 9 3 3 1

Factors of 18 = 2 x 3 x 3
Factors of 27 = 3 x 3 x 3
Multiply all the common factors of 18 and 27.
3 x 3 = 9
GCF(18, 27) = 9
12
Find the GCF of 8 and 12
4 is the GCF of 8 and 12
Factors of 8
 2 8 2 4 2 2 1
Factors of 12
 2 12 2 6 3 3 1

Factors of 8 = 2 x 2 x 2
Factors of 12 = 2 x 2 x 3
Multiply all the common factors of 8 and 12.
2 x 2 = 4
GCF(8, 12) = 4
13
Find the GCF of 9 and 12
3 is the GCF of 9 and 12
Factors of 9
 3 9 3 3 1
Factors of 12
 2 12 2 6 3 3 1

Factors of 9 = 3 x 3
Factors of 12 = 2 x 2 x 3
Multiply all the common factors of 9 and 12.
3 = 3
GCF(9, 12) = 3
14
Find the GCF of 6 and 8
2 is the GCF of 6 and 8
Factors of 6
 2 6 3 3 1
Factors of 8
 2 8 2 4 2 2 1

Factors of 6 = 2 x 3
Factors of 8 = 2 x 2 x 2
Multiply all the common factors of 6 and 8.
2 = 2
GCF(6, 8) = 2
15
Find the GCF of 8 and 10
2 is the GCF of 8 and 10
Factors of 8
 2 8 2 4 2 2 1
Factors of 10
 2 10 5 5 1

Factors of 8 = 2 x 2 x 2
Factors of 10 = 2 x 5
Multiply all the common factors of 8 and 10.
2 = 2
GCF(8, 10) = 2
16
Find the GCF of 12 and 15
3 is the GCF of 12 and 15
Factors of 12
 2 12 2 6 3 3 1
Factors of 15
 3 15 5 5 1

Factors of 12 = 2 x 2 x 3
Factors of 15 = 3 x 5
Multiply all the common factors of 12 and 15.
3 = 3
GCF(12, 15) = 3
17
Find the GCF of 12 and 18
6 is the GCF of 12 and 18
Factors of 12
 2 12 2 6 3 3 1
Factors of 18
 2 18 3 9 3 3 1

Factors of 12 = 2 x 2 x 3
Factors of 18 = 2 x 3 x 3
Multiply all the common factors of 12 and 18.
2 x 3 = 6
GCF(12, 18) = 6
18
Find the GCF of 12 and 16
4 is the GCF of 12 and 16
Factors of 12
 2 12 2 6 3 3 1
Factors of 16
 2 16 2 8 2 4 2 2 1

Factors of 12 = 2 x 2 x 3
Factors of 16 = 2 x 2 x 2 x 2
Multiply all the common factors of 12 and 16.
2 x 2 = 4
GCF(12, 16) = 4
19
Find the GCF of 6 and 9
3 is the GCF of 6 and 9
Factors of 6
 2 6 3 3 1
Factors of 9
 3 9 3 3 1

Factors of 6 = 2 x 3
Factors of 9 = 3 x 3
Multiply all the common factors of 6 and 9.
3 = 3
GCF(6, 9) = 3
20
Find the GCF of 24 and 36
12 is the GCF of 24 and 36
Factors of 24
 2 24 2 12 2 6 3 3 1
Factors of 36
 2 36 2 18 3 9 3 3 1

Factors of 24 = 2 x 2 x 2 x 3
Factors of 36 = 2 x 2 x 3 x 3
Multiply all the common factors of 24 and 36.
2 x 2 x 3 = 12
GCF(24, 36) = 12

## Worksheet: Find the GCF of 2 Numbers

Find the gcf of 2 numbers worksheet is the largest collection of practice problems and solved exercises which can be served as homework, classwork or assignment problems for the students to learn, practice, assess, iterate and master the skills of how to solve such divisors and factors problems in basic mathematics.

Online Test
00:00
Start my Challenge
Find the GCF of 54, 27, 18 and 63
Find the GCF of 64 and 56
Find the GCF of 40, 5, 15 and 10
Find the GCF of 36, 48, 30, 12 and 24
Find the GCF of 30, 45 and 75
Find the GCF of 21, 9, 27, 6 and 15
Find the GCF of 20, 60, 50, 40 and 70
Find the GCF of 12, 14, 2, 18 and 16
Find the GCF of 2, 6 and 20
Find the GCF of 2, 3 and 8

## Online Test: Find the GCF of 2 Numbers

This online test to find the gcf of 2 numbers is a formative assessment which can be used as homework, classwork or assignment problems to assess and improve the learner's math skills on divisors and factors.