Percentages · Usually met around P6
Percentages of an amount
Find 10% first, then double or halve.
How to do it
Method
Find 10% first, then double or halve
20% of 80: 10% is 8, 8 × 2 = 16
Another way
As a fraction
80 × 20100 = 16
In full
Find 10% first. That's ÷10, which moves the point one place left. 5% is half of 10%, and 20% is double 10%. 50% is half the whole, 25% is a quarter of the whole, and 75% is 50% + 25%. 25% of 80 → 80 ÷ 4 = 20. Or turn the percentage into a fraction and multiply: 25% of 80 = 80 × 25100 = 20.
Worked examples
Have a go first, then open each one for the answer and the working.
Example 1
10% of 60
Show the answer and working
Answer: 10% of 60 = 6
10% of 60: 10% is 60 ÷ 10 = 6
Example 2
10% of 300
Show the answer and working
Answer: 10% of 300 = 30
10% of 300: 10% is 300 ÷ 10 = 30
Example 3
50% of 80
Show the answer and working
Answer: 50% of 80 = 40
50% of 80: 50% is half the whole, 80 ÷ 2 = 40
Practise it in the game →Percentages · Free to start, unlimited questions, no download