A 25% then 10% discount is 32.5% off, not 35%.
Price at common discounts
How it works
Sale price = original × (1 − discount). Stacked discounts multiply: (1 − first) × (1 − second). Tax is charged on the sale price.
Is the "original" price real? Many sales start from a list price nobody pays. Is this a good price? compares an offer with what the same item sells for on eBay today and its 30-day low.
Questions
How do I calculate a percentage discount?
Multiply the price by the discount and subtract it, or multiply the price by one minus the discount. 25% off $120 is 120 × 0.75 = $90.
How do stacked discounts work?
Each discount applies to the price left after the one before. 25% off and then an extra 10% off gives 120 × 0.75 × 0.9 = $81, a 32.5% total discount, not 35%.
How do I find the percent off from two prices?
Divide the sale price by the original price and subtract from one. A $90 sale on a $120 item is 1 − 90/120 = 25% off.
Is the sale price a good deal?
Only if the original price is one people actually paid. Many "was" prices are list prices nobody charges; compare the sale with what the same item sells for elsewhere and with its recent low before you buy.