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Page 1: Maths (Addition, Subtraction and Multiplication)

Addition

Addition is when you have one number, '5' for example, and add it with another number, '4' for another example. 5+4=9. It can get very complicated and you can add more than two numbers together. If you are adding 10 to a one-digit number (0-9) you can just replace the zero in the ten with the one-digit number. Adding 0, however, doesn't change a number at all. If you want to undo an addition, you have to subtract.

Subtraction

Subtraction is the opposite of addition. Instead of combining two numbers together, you are taking a number away from a bigger one. if we want to subtract 5 from 9, we will show it as 9-5. If we take 5 away from 9, we will get 4, which can make 4+5=9. What helps in subtraction is number bonds, which are the numbers that add up to ten. If we do 10-7, we know that 7+3=10, so we can say 10-7=3.

Multiplication

Multiplication is more confusing than addition and subtraction, but it actually still uses addition. If we wanted to do 8x2, it would be the same as 8+8, or 2+2+2+2+2+2+2+2. Multiplying by 10 is easy though. You just need to replace the 1 in 10 with the number you are multiplying by. For example, 4x10=40. Below is a grid of all the multiplications from 1x1 to 10x10.

X 1 2 3 4 5 6 7 8 9 10
1 1 2 3 4 5 6 7 8 9 10
2 2 4 6 8 10 12 14 16 18 20
3 3 6 9 12 15 18 21 24 27 30
4 4 8 12 16 20 24 28 32 36 40
5 5 10 15 20 25 30 35 40 45 50
6 6 12 18 24 30 36 42 48 54 60
7 7 14 21 28 35 42 49 56 63 70
8 8 16 24 32 40 48 56 64 72 80
9 9 18 27 36 45 54 63 72 81 90
10 10 20 30 40 50 60 70 80 90 100

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