1. double times multiple Multiplication factor multiply
Find the product of
double

2. Where do we start?
Repeated addition
Arrays
Visualisation

3. Arrays 3 X 4

4. Repeated addition
4 x 3
= 12
+ 3
+ 3
+ 3
+ 3 6 9 3 12

5. I have four friends and I want to give them two sweets each, how many sweets will I need?
4 lots of 2 is 8
4 x 2 = 8

6. inverse
The inverse of multiplication is division
23 x 7 = 161
161 ÷ 7 = 23
161 ÷ 23 = 7

7. Multiplying by 10
H T U 3

8. H T U 2 7

9. H T U . t h 1 . 6 7

10. 3 x 70 =
210
40 x 60 =
2400

11. …and powers of 10
100 = 10 x 10
Move 2 places to the left
Move 3 places to the left
1 000 = 10 x 10 x 10

12. a × b = b × a Example: Commutative Laws
The "Commutative Laws" say we can swap numbers over and still get the same answer ...
a × b  =  b × a
Example:

13. Associative Laws
The "Associative Laws" say that it doesn't matter how we group the numbers (i.e. which we calculate first) ...
(a × b) × c  =  a × (b × c)

14. a × (b + c) = a × b + a × c Distributive Law
This is what it lets us do:
3 lots of (2+4) is the same as 3 lots of 2 plus 3 lots of 4
So, the 3× can be "distributed" across the 2+4, into 3×2 and 3×4
a × (b + c)  =  a × b  +  a × c

15. Try the calculations yourself:
3 × (2 + 4)  =  3 × 6  =  18
3×2 + 3×4  =   = 18

16. We get the same answer when we:
multiply a number by a group of numbers added together, or
multiply each separately then add them

18. "Factors" are the numbers you can multiply together to get another number:
2 and 3 are factors of 6

19. A number can have many factors.
1 x 12 =12
2 x 6 = 12
3 x 4 = 12

20. Finding the area of a rectangle
l x w = A
6 m
12 m²
2 m

21. SQUARE NUMBERS

22. Jottings
Crossing the tens boundary
17x5= (10x5=50, 7x5=35, 50+35=85)

23. Doubling

24. Written Methods x 10 3 4 40 12

25. x 30 8 5
150 40
190

28. 36x4= 36
X 4 2