The purpose of this activity is to support students in calculating prices after any percentage discount is applied.
Pose this problem:
You go to a shop and buy an item that usually costs $64. They give you a 12.5% off discount.
How much do you pay for the item? You might adapt this problem to include a more specific context that is more relevant to your students' interests, cultural backgrounds, and learning from other curriculum areas.
Draw this double number line model to represent the problem:
What percentage is taken off? (12.5%)
What percentage of the price do you pay? (87.5% since 100 – 12.5 = 87.5%)
How can you work out 12.5% of $64? (Methods include finding 10% then 5% then 2.5% or finding 50% then 25% then 12.5%)
What is 87.5% of $64? (12.5% of 64 = $8.00 so 87.5% of 64 = 64 – 8 = $76.00)
Develop the double number line as each question is answered, as shown below:
Next steps
Printed from https://nzmaths.co.nz/resource/more-complex-discounts at 9:54am on the 29th April 2024