# Greatest Common Factor of 3 Numbers Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to **Greatest Common Factor of 3 Numbers**. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using **Show Answer** button. You can use **Next Quiz** button to check new set of questions in the quiz.

### Answer : A

### Explanation

**Step 1:**

The prime factorization of 18 is

18 = 2 × 3 × 3

The prime factorization of 30 is

30 = 2 × 3 × 5

The prime factorization of 45 is

45 = 3 × 3 × 5

**Step 2:**

The greatest common factor of 18, 30 and 45 is therefore 3.

### Answer : B

### Explanation

**Step 1:**

The prime factorization of 21 is

21 = 3 × 7

The prime factorization of 36 is

36 = 2 × 2 × 3 × 3

The prime factorization of 42 is

42 = 2 × 3 × 7

**Step 2:**

The greatest common factor of 21, 36 and 42 is therefore 3.

### Answer : D

### Explanation

**Step 1:**

The prime factorization of 24 is

24 = 2 × 2 × 2 × 3

The prime factorization of 32 is

32 = 2 × 2 × 2 × 2 × 2

The prime factorization of 48 is

48 = 2 × 2 × 2 × 2 × 3

**Step 2:**

The greatest common factor of 24, 32 and 48 is therefore 8.

### Answer : C

### Explanation

**Step 1:**

The prime factorization of 26 is

26 = 2 × 13

The prime factorization of 52 is

52 = 2 × 2 × 13

The prime factorization of 78 is

78 = 2 × 3 × 13

**Step 2:**

The greatest common factor of 26, 52 and 78 is therefore 26.

### Answer : A

### Explanation

**Step 1:**

The prime factorization of 28 is

28 = 2 × 2 × 7

The prime factorization of 49 is

49 = 7 × 7

The prime factorization of 84 is

84 = 2 × 2 × 3 × 7

**Step 2:**

The greatest common factor of 28, 49 and 84 is therefore 7.

### Answer : B

### Explanation

**Step 1:**

The prime factorization of 36 is

36 = 2 × 2 × 3 × 3

The prime factorization of 48 is

48 = 2 × 2 × 2 × 2 × 3

The prime factorization of 120 is

120 = 2 × 2 × 2 × 3 × 5

**Step 2:**

The greatest common factor of 36, 48 and 120 is therefore 12.

### Answer : D

### Explanation

**Step 1:**

The prime factorization of 34 is

34 = 2 × 17

The prime factorization of 85 is

85 = 5 × 17

The prime factorization of 136 is

136 = 2 × 2 × 2 × 17

**Step 2:**

The greatest common factor of 34, 85 and 136 is therefore 17.

### Answer : C

### Explanation

**Step 1:**

The prime factorization of 36 is

36 = 2 × 2 × 3 × 3

The prime factorization of 60 is

60 = 2 × 2 × 3 × 5

The prime factorization of 144 is

144 = 2 × 2 × 2 × 2 × 3 × 3

**Step 2:**

The greatest common factor of 36, 60 and 144 is therefore 12.

### Answer : A

### Explanation

**Step 1:**

The prime factorization of 72 is

72 = 2 × 2 × 2 × 3 × 3

The prime factorization of 96 is

96 = 2 × 2 × 2 × 2 × 2 × 3

The prime factorization of 180 is

180 = 2 × 2 × 3 × 3 × 5

**Step 2:**

The greatest common factor of 72, 96 and 180 is therefore 12.

### Answer : B

### Explanation

**Step 1:**

The prime factorization of 90 is

90 = 2 × 3 × 3 × 5

The prime factorization of 150 is

150 = 2 × 3 × 5 × 5

The prime factorization of 225 is

225 = 3 × 3 × 5 × 5

**Step 2:**

The greatest common factor of 90, 150 and 225 is therefore 15.