Posted: October 16, 2018

**page 61**

3. Which of the following numbers are factors of 80? 2, 3, 4, 5, 6, 8, 9, 10

8. Group these numbers into prime numbers and composite numbers: 59, 93, 97, 87, 73, 45

10. Which numbers from 70 to 80 are prime numbers?

11. How many dates in September are prime numbers? How many are composite numbers? List them all in each group.

**page 65**

1. Using a Venn diagram, show the factors of 18 and 24, and then the common factors of 18 and 24.

2. List the common factors of each pair of numbers:

a) 15, 25 b) 16, 40 c) 18, 42 d) 35, 60

3. Find the factors of each number and put them into a "factor rainbow".

a) 48 b) 50 c) 78 d) 62

4. List the factors for each number. Group these factors into prime numbers and composite numbers.

a) 34 b) 40 c) 72 d) 94

5. Make a "factor tree" to find the prime factors of each number.

a) 64 b) 85 c) 90 d) 76

8. Fill in the "factor trees" with a combination of numbers that works.

**I suspect these last 2 questions will be the most challenging, but we have practiced questions like the others a lot in class so the rest should be straight forward. **