1. Percentages
Level 8

2. Using the Decimal Multiplier to Find Percentages.
Example: Find 12% of £54?
Decimal = 12% = 12 = 12 ÷ 100 = 0.12
multiplier
On calculator:
0.12 x 54 =
= £6.48

3. Percentage Increase Example: Increase £24 000 by 3%
3% of % of
103% of
= 103 x
100
= 1.03 x
= £24 720

4. Percentage Decrease Example: Reduce £17.60 by 15%
15% of £17.60 – answer from £17.60
100% of £17.60 – 15% 0f £17.60
85% of £17.60 (100% - 15% = 85%)
= 0.85 x = £14.96

5. What do you…… Multiply a quantity by if it increased by
a) 6% b) 9% c) 17.5% d) 1.25%
a) 1.06 b) 1.09 c) d)
Multiply a quantity by if it is decreased by
a) 6% b) 9% c) 17.5% d) 1.25%
a) 0.94 b) 0.91 c) d)

6. Finding the original amount
Example: John received a 20% increase in his annual salary. His new salary was £ What was his salary before the rise?
% increase – John’s original salary has been x 1.2 to get £
x 1.2
Salary after
rise £31 260
Salary before
rise?
÷ 1.2
÷ 1.2 = £26 050

7. Finding the original amount
Example: There was a 25% discount in a sale. A boy paid £30 for a pair of jeans in the sale. What was the original price of the jeans?
% decrease - £30 has been x 0.75 to get the reduced price.
x 0.75
Price after
Discount £30
Price before
Discount?
30 ÷ 0.75 = £40
÷ 0.75

8. Turn to page 188 Complete exercise 6.1A and 6.1B Start at question 3
Show all your working out DON’T just write the answer.
You must complete both exercises before the end of the lesson
When you finish turn to page 189 and start exercise 6.2A. Complete all questions.