Answer: 259.20 dollars
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Explanation:
When you have a 10% discount, the customer pays the remaining 90% of the original cost (note how the percentages add to 100%)
The decimal form of 90% is 0.90
When you apply a 20% discount, then the customer pays the remaining 80% which converts to 0.80
Chaining these discounts together means the final multiplier will be 0.90*0.80 = 0.72 which means that the customer is paying 72% of the original price when both discounts are applied at the same time. The order of the discounts doesn't matter because we can multiply in any order.
If the item was originally $360 before either discount kicks in, then the final price is 0.72*360 = 259.20 dollars
Side note: the final discount rate is 100% - 72% = 28% (it's fairly close to 30% but not quite there; so we can't simply just add the 10% and 20% to get 30%)
