3.2 Proportion

• What is the definition of proportion?

  Equal relationship between ratios
• In inverse proportion, as one quantity increases, the other quantity decreases proportionally.

  True
• What happens to the second quantity in inverse proportion if the first quantity increases?

  It decreases proportionally
• The ratios 1:3 and 2:5 are not equivalent.


  True
• In a direct proportion, the ratio of the quantities is constant
• To identify equivalent ratios, we need to check if the ratio of the quantities is the same
• In inverse proportion, the product of the quantities is constant
• If a recipe requires 2 cups of flour for 4 servings, then 4 cups are needed for 8 servings.
• In direct proportion, as one quantity increases, the other quantity increases
• If 2 workers can complete a task in 8 hours, then 4 workers can complete it in 4 hours.
• Equivalent ratios represent the same proportional relationship.
• Match the property with the type of proportion:

  Definition ↔️ As one increases, the other decreases

  Example ↔️ 2 workers complete task in 8 hours, 4 workers in 4 hours

  Ratio Relationship ↔️ Ratio of quantities is inverse
• In inverse proportion, the ratio of the quantities is inverse
• Steps to solve a proportion problem using cross-multiplication

  1️⃣ Set up the proportion

  2️⃣ Cross-multiply

  3️⃣ Solve for the unknown
• In inverse proportion, the product of the quantities remains constant.

  True
• If 5 workers complete a project in 20 days, then 10 workers will complete it in 10 days.
• Give an example of direct proportion.

  3 apples cost £1.50, 6 cost £3.00
• What happens to the second quantity in direct proportion if the first quantity increases?

  It increases proportionally
• Are the ratios 3:6 and 4:8 equivalent?

  Yes
• To identify equivalent ratios, we check if the ratio of the quantities is the same.
• Equivalent ratios represent the same proportional relationship.


  True
• In direct proportion, the ratio between quantities is constant.

  True
• In direct proportion, the ratio between the quantities is constant
• An investment of £1,000 yields a return of £100, so £2,000 yields a return of £200.