1. A Guide to succeeding at Arithmetic

2. First, you must understand place value…
Place value is the value of each
digit in a number. It means
understanding that 582 is made
up of 500, 80 and 2
H T U

3. Remember to use the correct number operation
Remember, when setting these questions out, to ensure the units, 10, 100s and 1000s are all underneath each other.
And don’t forget to exchange
if the top digit is smaller than
the one below it. 6 1
Remember to use the correct number operation

4. Place value applies to decimals too.
T U . t 9 1
1 0 1

5. It’s important to know square and cubed numbers too.
A square number
is a number multiplied
by itself
A cubed number
is a number multiplied
by itself three times
62 = 6 x 6 = 3 6
= 4 6
43 = 4 x 4 x 4 = 64
4 6

6. Multiplication calculations will always come up, so it is ESSENTIAL that you know ALL of your times tables and have QUICK recall.
5 x 4 = x =

7. If you know your times tables, it makes answering questions like these so much quicker!
REMEMBER your place holder
When multiplying by a multiple
of 10

8. If there’s a multiplication problem with a decimal place, take the decimal point out, then add it back in later…
Remove the
decimal point
3 . 9
3 9
3 .9
x 3 0
x 3 0
x 3 0
Then add back in,
ensuring that you do
the same to the answer.
1 1 7

9. Long division – with a large number, it helps to find the first few multiples and jot these down.
1) How many 43s
are there in 64? 1 5 21 43 86
129
172
215
2 marks. You can get 1 mark for your calculations!
2) How many 43s
are in 215?
1 5

10. When adding or subtracting fractions, find a common denominator
When adding or subtracting fractions, find a common denominator. If you change a denominator, change the numerator too! x3 5 15
This can then
be simplified = 7 21 x3 ÷3 15 3 18 6 + = = 21 21 21 7 6 ÷3 7

11. When multiplying fractions, x the numerators, then the denominators.÷6 12 2 30 5 ÷6 2 5

12. When dividing fractions, use KFC (keep, flip, change)1 2 ÷ 1 1 1 x = 4 1 4 2 8
Keep 1
Change 8

13. To find a fraction of a number, divide by the denominator then multiply by the numerator
140 ÷ 5 = 28
28 x 2 = 56
Multiply by the numerator 56

14. To find a percentage when the % is a multiple of 10 (e
To find a percentage when the % is a multiple of 10 (e.g 10%, 20%, etc)
Divide the amount
by 10 to find 10%
1800 ÷ 10 = 180
180 x 2 = 360
360
Then x the answer
by the number of 10s

15. To find a percentage of an amount which ISN’T a multiple of 10, first find 1% by ÷ 100, then x by the percentage.
This gives
REMEMBER
per cent means
out of 100
650 ÷ 100 = 6.5
This gives us 1%
6.5
x 2 8
This gives
us 28%
1 8 2
1 8 2