Written Instructions:
For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..
For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.
Leave your answers in the simplest form or correct to two decimal places.
| 1) What is the greatest common factor of 20 and 16
Answer:_______________ |
| 2) What is the greatest common factor of 9 and 16
Answer:_______________ |
| 3) What is the greatest common factor of 20 and 14
Answer:_______________ |
| 4) What is the greatest common factor of 18 and 4
Answer:_______________ |
| 5) What is the greatest common factor of 8 and 19
Answer:_______________ |
| 6) What is the greatest common factor of 18 and 12
Answer:_______________ |
| 7) What is the greatest common factor of 9 and 18
Answer:_______________ |
| 8) What is the greatest common factor of 2 and 14
Answer:_______________ |
| 9) What is the greatest common factor of 2 and 16
Answer:_______________ |
| 10) What is the greatest common factor of 2 and 6
Answer:_______________ |
| 1) What is the greatest common factor of 20 and 16 Answer: 4 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 20 = 2 × 2 × 5 16 = 2 × 2 × 2 × 2 Next, find the common factors shared by both of the numbers. 20 = 2 × 2 × 5 16 = 2 × 2 × 2 × 2 Finally, multiply the common factors to find the greatest common factor. 2 × 2 = 4 The greatest common factor of 20 and 16 is 4. |
| 2) What is the greatest common factor of 9 and 16 Answer: 1 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Write the prime factorisation for each number. 9 = 3 × 3 16 = 2 × 2 × 2 × 2 Next, find the common factors shared by both of the numbers. 9 = 3 × 3 16 = 2 × 2 × 2 × 2 There are no common factors here. However, 1 is a factor of every whole number. So, the greatest common factor of 9 and 16 is 1. |
| 3) What is the greatest common factor of 20 and 14 Answer: 2 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 20 = 2 × 2 × 5 14 = 2 × 7 Next, find the common factors shared by both of the numbers. 20 = 2 × 2 × 5 14 = 2 × 7 The only common factor of 20 and 14 is 2, so the greatest common factor is 2. |
| 4) What is the greatest common factor of 18 and 4 Answer: 2 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 18 = 2 × 3 × 3 4 = 2 × 2 Next, find the common factors shared by both of the numbers. 18 = 2 × 3 × 3 4 = 2 × 2 The only common factor of 18 and 4 is 2, so the greatest common factor is 2. |
| 5) What is the greatest common factor of 8 and 19 Answer: 1 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 19 is a prime number. You do not need to factorise 19. 8 = 2 × 2 × 2 19 Next, find the common factors shared by both of the numbers. 8 = 2 × 2 × 2 19 = 19 There are no common factors here. However, 1 is a factor of every whole number. So, the greatest common factor of 8 and 19 is 1. |
| 6) What is the greatest common factor of 18 and 12 Answer: 6 SOLUTION 1 : Reember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 18 = 2 × 3 × 3 12 = 2 × 2 × 3 Next, find the common factors shared by both of the numbers. 18 = 2 × 3 × 3 12 = 2 × 2 × 3 Finally, multiply the common factors to find the greatest common factor. 2 × 3 = 6 The greatest common factor of 18 and 12 is 6. |
| 7) What is the greatest common factor of 9 and 18 Answer: 9 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 9 = 3 × 3 18 = 2 × 3 × 3 Next, find the common factors shared by both of the numbers. 9 = 3 × 3 18 = 2 × 3 × 3 Finally, multiply the common factors to find the greatest common factor. 3 × 3 = 9 The greatest common factor of 9 and 18 is 9. |
| 8) What is the greatest common factor of 2 and 14 Answer: 2 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 2 is a prime number. You do not need to factorise 2. 2 14 = 2 × 7 Next, find the common factors shared by both of the numbers. 2 = 2 14 = 2 × 7 The only common factor of 2 and 14 is 2, so the greatest common factor is 2. |
| 9) What is the greatest common factor of 2 and 16 Answer: 2 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 2 is a prime number. You do not need to factorise 2. 2 16 = 2 × 2 × 2 × 2 Next, find the common factors shared by both of the numbers. 2 = 2 16 = 2 × 2 × 2 × 2 The only common factor of 2 and 16 is 2, so the greatest common factor is 2. |
| 10) What is the greatest common factor of 2 and 6 Answer: 2 SOLUTION 1 : Remember: The greatest common factor is the greatest whole number that is a factor of each of two or more numbers. Solve: Write the prime factorisation for each number. 2 is a prime number. You do not need to factorise 2. 2 6 = 2 × 3 Next, find the common factors shared by both of the numbers. 2 = 2 6 = 2 × 3 The only common factor of 2 and 6 is 2, so the greatest common factor is 2. |