Year 8 Maths Ratios and Proportions: Worked Examples

Year 8 maths ratio and proportion: what to know

This practical guide explains Year 8 maths ratio and proportion through examples, checks and realistic next steps for students and parents.

Ratio versus proportion: what changes?

A ratio compares quantities, such as 2 red counters to 3 blue counters (2:3). Proportion describes two quantities changing at matching rates, such as doubling a recipe while keeping ingredient ratios constant.

Example 1: simplify a ratio

There are 12 red counters and 18 blue counters. The ratio red:blue is 12:18. Divide both parts by 6 to get 2:3. Check the order of words in the question.

Example 2: share an amount

Share AED 150 in the ratio 2:3. Total parts = 5. One part = AED 30. The shares are 2 × 30 = AED 60 and 3 × 30 = AED 90.

Example 3: scale a recipe

A recipe needs 200 g of flour for four servings. For ten servings, multiply by 10/4 = 2.5. Flour needed = 500 g. Label the units to reduce mistakes.

Example 4: unit rate

Three notebooks cost AED 24. Each notebook costs AED 8, so seven notebooks cost AED 56 at the same rate. First divide to find the cost of one.

Six-question practice set

1. Simplify 9:15.
2. Share AED 80 in the ratio 1:3.
3. A 2:5 ratio has 8 in the first part; find the second.
4. Five pens cost AED 35; find the price of eight.
5. Scale 300 mL for three servings to five servings.
6. Explain why 2:3 equals 6:9.

Answers: 3:5; AED 20 and AED 60; 20; AED 56; 500 mL; both parts were multiplied by 3.

An easy parent check

Ask students whether their solution makes practical sense: if the quantity of servings increases, the ingredient amount should increase too. For additional guidance, explore Maths tutoring options in Abu Dhabi and compare the approach in our companion Year 7 fractions article.

Questions parents and students ask