Is it really a bargain?

Many shops and supermarkets express money-off deals in fractions, for example something might be half-price, or even 75% off.

But wait? Isn’t that a percentage? Yes, but did you know that fractions can be expressed as percentages, decimals and even ratios. They’re all ‘fractions of a whole’. 75% off is just another way of saying 75-hundredths. This activity is something you can do as part of your weekly shop.

Things you need

Shopping or grocery trip.

The challenge

Next time you go to a shop or supermarket and spot a sale sign, stop.

Ask your child to consider whether this price is good value for money. Calculate the discount.

For example, let’s say a roast chicken costs $12. It's been marked down by one-quarter (or 25%). How much does it cost after the discount? If you bought the chicken at its new price, what could you afford to buy for dessert with the savings?

The conversation

"When you hear one-quarter or 25% off, does one sound like a better deal than the other?"
"If this packet of toilet paper is half-price, do you think we are better off buying two of them, or should we use the money we've saved to buy something else?"
"This is like that episode of the ABC's Teenage Boss. Let's watch it together and you can help me make the shopping budget and find discounts."

Working with fractions helps us work with money, and helps with lots of careers too. Artists, sports coaches, teachers, builders, chefs, nurses and doctors all use knowledge about fractions as part of their day-to-day working lives.

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