Math Practice Online > free > lessons > California > 5th grade > Greatest Common Factor

These sample problems below for Greatest Common Factor were generated by the MathScore.com engine.

## Sample Problems For Greatest Common Factor

### Complexity=8

Find the greatest common factor of each pair of numbers.
 1.   5, 7 2.   4, 6

### Complexity=12

Find the greatest common factor of each pair of numbers.
 1.   6, 3 2.   10, 4

### Complexity=20

Find the greatest common factor of each pair of numbers.
 1.   12, 15 2.   8, 12

### Complexity=30

Find the greatest common factor of each pair of numbers.
 1.   20, 24 2.   24, 20

### Complexity=40

Find the greatest common factor of each pair of numbers.
 1.   36, 39 2.   24, 18

### Complexity=50

Find the greatest common factor of each pair of numbers.
 1.   45, 48 2.   50, 35

### Complexity=80

Find the greatest common factor of each pair of numbers.
 1.   48, 57 2.   80, 64

### Complexity=150

Find the greatest common factor of each pair of numbers.
 1.   108, 96 2.   132, 108

### Complexity=8

Find the greatest common factor of each pair of numbers.
15, 7
Solution
The factors of 5 are 1, 5.
From greatest to least, check if each factor divides evenly into 7.
5 does not divide evenly into 7.
1 divides evenly into 7. Therefore, 1 is the GCF.

Factors of 5: 1, 5
Factors of 7: 1, 7

24, 6
Solution
6 - 4 = 2. Does 2 divide evenly into 4? Yes. Therefore 2 is the GCF.

Factors of 4: 1, 2, 4
Factors of 6: 1, 2, 3, 6

### Complexity=12

Find the greatest common factor of each pair of numbers.
16, 3
Solution
3 divides evenly into 6. Therefore 3 must be the greatest common factor.

Factors of 6: 1, 2, 3, 6
Factors of 3: 1, 3

210, 4
Solution
10 - 4 = 6. GCF(10,4) = GCF(4, 6).
The difference between 4 and 6 is 2. Does 2 divide evenly into 6? Yes. Therefore 2 is the GCF.

Factors of 10: 1, 2, 5, 10
Factors of 4: 1, 2, 4

### Complexity=20

Find the greatest common factor of each pair of numbers.
112, 15
Solution
15 - 12 = 3. Does 3 divide evenly into 12? Yes. Therefore 3 is the GCF.

Factors of 12: 1, 2, 3, 4, 6, 12
Factors of 15: 1, 3, 5, 15

28, 12
Solution
12 - 8 = 4. Does 4 divide evenly into 8? Yes. Therefore 4 is the GCF.

Factors of 8: 1, 2, 4, 8
Factors of 12: 1, 2, 3, 4, 6, 12

### Complexity=30

Find the greatest common factor of each pair of numbers.
120, 24
Solution
24 - 20 = 4. Does 4 divide evenly into 20? Yes. Therefore 4 is the GCF.

Factors of 20: 1, 2, 4, 5, 10, 20
Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24

224, 20
Solution
24 - 20 = 4. Does 4 divide evenly into 20? Yes. Therefore 4 is the GCF.

Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24
Factors of 20: 1, 2, 4, 5, 10, 20

### Complexity=40

Find the greatest common factor of each pair of numbers.
136, 39
Solution
39 - 36 = 3. Does 3 divide evenly into 36? Yes. Therefore 3 is the GCF.

Factors of 36: 1, 2, 3, 4, 6, 9, 12, 18, 36
Factors of 39: 1, 3, 13, 39

224, 18
Solution
24 - 18 = 6. Does 6 divide evenly into 18? Yes. Therefore 6 is the GCF.

Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24
Factors of 18: 1, 2, 3, 6, 9, 18

### Complexity=50

Find the greatest common factor of each pair of numbers.
145, 48
Solution
48 - 45 = 3. Does 3 divide evenly into 45? Yes. Therefore 3 is the GCF.

Factors of 45: 1, 3, 5, 9, 15, 45
Factors of 48: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48

250, 35
Solution
The factors of 35 are 1, 5, 7, 35.
From greatest to least, check if each factor divides evenly into 50.
35 does not divide evenly into 50.
7 does not divide evenly into 50.
5 divides evenly into 50. Therefore, 5 is the GCF.

Factors of 50: 1, 2, 5, 10, 25, 50
Factors of 35: 1, 5, 7, 35

### Complexity=80

Find the greatest common factor of each pair of numbers.
148, 57
Solution
The factors of 48 are 1, 2, 3, 4, 6, 8, 12, 16, 24, 48.
From greatest to least, check if each factor divides evenly into 57.
48 does not divide evenly into 57.
24 does not divide evenly into 57.
16 does not divide evenly into 57.
12 does not divide evenly into 57.
8 does not divide evenly into 57.
6 does not divide evenly into 57.
4 does not divide evenly into 57.
3 divides evenly into 57. Therefore, 3 is the GCF.

Factors of 48: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48
Factors of 57: 1, 3, 19, 57

280, 64
Solution
80 - 64 = 16. Does 16 divide evenly into 64? Yes. Therefore 16 is the GCF.

Factors of 80: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80
Factors of 64: 1, 2, 4, 8, 16, 32, 64

### Complexity=150

Find the greatest common factor of each pair of numbers.
1108, 96
Solution
108 - 96 = 12. Does 12 divide evenly into 96? Yes. Therefore 12 is the GCF.

Factors of 108: 1, 2, 3, 4, 6, 9, 12, 18, 27, 36, 54, 108
Factors of 96: 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 96

2132, 108
Solution
The factors of 108 are 1, 2, 3, 4, 6, 9, 12, 18, 27, 36, 54, 108.
From greatest to least, check if each factor divides evenly into 132.
108 does not divide evenly into 132.
54 does not divide evenly into 132.
36 does not divide evenly into 132.
27 does not divide evenly into 132.
18 does not divide evenly into 132.
12 divides evenly into 132. Therefore, 12 is the GCF.

Factors of 132: 1, 2, 3, 4, 6, 11, 12, 22, 33, 66, 132
Factors of 108: 1, 2, 3, 4, 6, 9, 12, 18, 27, 36, 54, 108

MathScore.com

Copyright Accurate Learning Systems Corporation 2008.