Year 8: Evaluate percentages

This cheat sheet will help you quickly and accurately calculate percentages in your Year 8 Maths lessons.

Key Concepts

• Percentage: A way of expressing a number as a fraction of 100. (e.g., 50% means 50 out of 100)
• Percentage = (Part / Whole) x 100

Calculating percentages

Finding a percentage of a number

1. Example 1: Find 20% of $60.
2. 1. Identify the part $\left(20\right)$ and the whole ($60).
3. 2. Write the equation: $(20/100)x$ $60
4. 3. Calculate: $\left(0.20\right)x$ $60 = $12
5. Answer: 20% of $60 is $12
6. Example 2: Find 75% of 80.
7. 1. Identify the part $\left(75\right)$ and the whole $\left(80\right)$.
8. 2. Write the equation: $(75/100)x80$
9. 3. Calculate: $\left(0.75\right)x80$ = $60
10. Answer: 75% of 80 is $60

Calculating the percentage of a number

To find the percentage of a number, use the formula: Percentage = (Part / Whole) x 100. Make sure your answer is expressed as a percentage (use the % symbol).

Don't forget to convert decimals to percentages by multiplying by 100.