Expressing Quantities as Percentages

This subtopic writes one quantity as a percentage of another: form the fraction in the same units, then multiply by 100%. In NSW Year 7 maths (NESA outcome MA4‑FRC‑C‑01) it is how test marks, discounts and price changes are compared fairly.

You will convert units first (45 minutes of 2 hours is 37.5%), give exact answers using fractions where needed, and choose the right whole, such as the old price for a discount. Comparing 42 out of 50 (84%) with 51 out of 60 (85%) shows which test result was better. This subtopic is part of Year 7 Percentages.