Step 7 Objective
Use the equivalence of fractions, decimals and percentages to compare proportions; calculate percentages and find the outcome of a given percentage increase or decrease.
- Examples of what pupils should
know and be able to do - Probing questions
- What if pupils find
this a barrier?
Examples of what pupils should know and be able to do
Convert fraction and decimal operators to percentage operators by multiplying by 100. For example:
- 0.45 0.45 × 100% = 45%
(7 ÷ 12) × 100% = 58.3% (1 d.p.)
Continue to use mental methods for finding percentages of quantities.
Use written methods:
Using an equivalent fraction
- 13% of 48
× 48 = 
= 6.24
Using an equivalent decimal
- 13% of 48
0.13 × 48 = 6.24
Using a unitary method
- 13% of 48
1% of 48 = 0.48
13% of 48 = 0.48 × 13 = 6.24
Find the outcome of a given percentage increase or decrease, for example:
An increase of 15% on an original cost of £12 gives a new price of
£12 × 1.15 = £13.80
or
15% of £12 = £1.80
£12 + £1.80 = £13.80