1. 9 x 14 9 x 12 Calculate the value of the following: 1 4 × 8 =
Starter: Answer the questions below in your books
Calculate the value of the following:
1 4 × 8 =
(9 + 3) × 6 =
(24 ÷ 4) × (17 – 9) =
7 × (32 ÷ 4) =
20 × 24 =
25 × 51 =
9 x 14
9 x 12

2. 9 x 14 9 x 12 Mark your answers: 1 4 × 8 = 32 (9 + 3) × 6 = 72
Starter: Answer the questions below in your books
Mark your answers:
1 4 × 8 = 32
(9 + 3) × 6 = 72
(24 ÷ 4) × (17 – 9) = 48
7 × (32 ÷ 4) = 56
20 × 24 = 480
25 × 51 = 1275
9 x 14
9 x 12

3. Break a number down into prime factors
2,3,5,7
Find the prime factors of a number and write it correctly.
Know what a prime number and a factor is.
Find the factors and prime factors of a number.

4. Remember: a prime number is any number that has exactly two factors
Remember: a prime number is any number that has exactly two factors. Prime numbers are really important in mathematics as they form the building blocks of the whole subject.
Remember: factors are numbers that go into another number. They are always integers (which is a mathematical word for whole numbers). You can think of them as the times tables which contain the final number.
So: a prime factor is a factor of a number which also happens to be a prime number.

5. 1 × 48=
2 × 24=
3 × 16=
4 × 12=
6 × 8=
2 × 6 × 4 =
2 × 3 × 8 =
3 × 4 × 4 =
4 × 3 × 4 =
6 × 2 × 4 =
2 × 3 × 2 × 4 =
2 × 3 × 2 × 4 =
3 × 2 × 2 × 4 =
2× 2 × 3 × 4 =
2 × 3 × 2 × 2 × 2 =
2 × 3 × 2 × 2 × 2 =
3 × 2 × 2 × 2 × 2 =
2× 2 × 3 × 2 × 2 =
48 =
2 × 2 × 2 × 2 × 3=
24 × 3

6. Draw a diagram like the one above, but this time, split 24 into 2×12 or 3×8. Then split each of those numbers up and then again until you get down to the prime factors. What do you notice?
How many different ways can you work out the prime factors of 36?
How many different ways can you work out the prime factors of 45?

7. The answers are next…

8. Prime factors of 24.
24 = 23 × 3

9. Factors of 36:
22 × 32 = 36

10. Factors of 45:
32 × 5 = 45