MathIsland
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−%Discounts Lab

30% + 20% off is not 50% off

Why does this exist?

Discounts stack by multiplication, not addition. See the true size of a double discount.

🔬 The interactive lab is live — currently in Korean

Sliders and simulations speak every language. Most visitors can follow the experiment even without reading Korean — and a full English version of this lab is on the way.

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