# Greatest Common Factor of 2 Numbers Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to **Greatest Common Factor of 2 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 12 is

12 = 2 × 2 × 3

The prime factorization of 21 is

21 = 3 × 7

**Step 2:**

The greatest common factor of 12 and 21 is therefore 3.

### Answer : B

### Explanation

**Step 1:**

The prime factorization of 15 is

15 = 3 × 5

The prime factorization of 24 is

24 = 2 × 2 × 2 × 3

**Step 2:**

The greatest common factor of 15 and 24 is therefore 3.

### Answer : C

### Explanation

**Step 1:**

The prime factorization of 52 is

52 = 2 × 2 × 13

The prime factorization of 130 is

130 = 2 × 5 × 13

**Step 2:**

The greatest common factor of 52 and 130 is therefore = 2 × 13 = 26.

### Answer : B

### Explanation

**Step 1:**

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 85 and 136 is therefore 17.

### Answer : D

### Explanation

**Step 1:**

The prime factorization of 64 is

64 = 2 × 2 × 2 × 2 × 2 × 2

The prime factorization of 120 is

120 = 2 × 2 × 2 × 3 × 5

**Step 2:**

The greatest common factor of 64 and 120 is therefore 8.

### Answer : A

### Explanation

**Step 1:**

The prime factorization of 56 is

56 = 2 × 2 × 2 × 7

The prime factorization of 72 is

72 = 2 × 2 × 2 × 3 × 3

**Step 2:**

The greatest common factor of 56 and 72 is therefore 8.

### Answer : C

### Explanation

**Step 1:**

The prime factorization of 65 is

65 = 5 × 13

The prime factorization of 117 is

117 = 3 × 3 × 13

**Step 2:**

The greatest common factor of 65 and 117 is therefore 13.

### Answer : D

### Explanation

**Step 1:**

The prime factorization of 81 is

81 = 3 × 3 × 3 × 3

The prime factorization of 216 is

216 = 2 × 2 × 2 × 3 × 3 × 3

**Step 2:**

The greatest common factor of 81 and 216 is therefore 27.

### Answer : B

### Explanation

**Step 1:**

The prime factorization of 75 is

75 = 3 × 5 × 5

The prime factorization of 180 is

180 = 2 × 2 × 3 × 3 × 5

**Step 2:**

The greatest common factor of 75 and 180 is therefore 15.

### Answer : A

### Explanation

**Step 1:**

The prime factorization of 36 is

36 = 2 × 2 × 3 × 3

The prime factorization of 150 is

150 = 2 × 3 × 5 × 5

**Step 2:**

The greatest common factor of 36 and 150 is therefore 6.