Best Buy

MathematicsAQAEdexcelGCSEUnit: Ratio & Proportion
Free taster
5 of 6 sections open
The basics

What Is a Best Buy?

What Is a Best Buy?

You're in the supermarket with £10. Two bottles of cola: 500ml for £1.50 or 750ml for £2.00. Which is better value? Best buy questions help you make smart shopping decisions by comparing the cost per unit - the price for each millilitre, gram, or item.
Best buy comparison showing price per unit calculations: 500ml for £1.50 = 0.3p per ml vs 750ml for £2.00 = 0.267p per ml, showing the larger bottle is better value
What does BOGOF mean?: Buy One Get One Free. You pay for 1 item but get 2 items. Price per item = Normal price ÷ 2.
Key terms

Mathematics glossary

What does BOGOF mean?
Buy One Get One Free. You pay for 1 item but get 2 items. Price per item = Normal price ÷ 2.
What does 'best buy' mean?
The option that gives the lowest cost per unit (per gram, per litre, per item). Calculate by dividing total price by quantity.

Now try it yourself

Quiz · Question 1 of 12

Which method correctly compares the value of two products?

Tap an answer to check it

Revise every Mathematics topic, free during alpha

Best Buy is one of 127 topics on PrepWise — all aligned to your exam board.

Start revising free →