What is 15% of 80 euros? And why is that different from paying 68 euros? Understand the connection, then practise independently.
Three ideas to start with.
Base G
The whole: €80 represents 100%.
Percentage p
The share out of a hundred: 15% = 15 / 100 = 0.15.
Percentage value W
The share as an amount: €80 × 0.15 = €12.
W = G × p / 100
For a discount, subtract the percentage value from the base. New price = €80 − €12 = €68. Cross-check: 85% of the original price remains; €80 × 0.85 = €68.
Three common mistakes.
Mixing percentages and euros: 15% off €80 is €12, not €15.
Mixing discount and final price: €12 is subtracted; €68 is paid.
Assuming changes cancel: a 20% decrease followed by a 20% increase does not restore the original value. €100 becomes €80, then €96. The second base is different.
TRY IT YOURSELF
The next step is yours.
Find the price after the discount. Answers are checked only in this browser; entries are neither stored nor transmitted.
With a 0% discount, the original price remains. With 100% off, the remaining price is €0. A higher discount on the same base should produce a lower final price. Round monetary amounts to cents at the end.
These calculations and results were checked during preparation and with automated arithmetic tests. No external pedagogical review. Updated 20 September 2026.
