Another way to think about it: for every 100 units in 10, you take 89. That adds up to 8.9.
89% of 10 equals 8.9. This applies to discounts, tips, taxes, interest rates, or any scenario where you need 89 out of every 100 parts of 10.
Whether you are calculating a discount, a tax, a tip, or a commission, the math is always the same: multiply 10 by 0.89.