Discounted selling price:
what you pay after a percentage off

The multiplier method

A discount of 20% means you pay the other 80%. Writing the price as list price × 0.80 gets the sale price in one step and avoids the two-step habit of calculating the discount amount and then subtracting. The multiplier is simply 1 minus the discount written as a decimal.

If you also want the discount amount on its own, multiply the list price by the rate: 2500 × 0.20 = ₹500. Selling price plus discount amount always gives back the list price, which is a quick check.

Common discounts on ₹2,500

Every 5% off this price takes ₹125 away, because 5% of ₹2,500 is ₹125. For a different list price, the pattern scales: halve the price and every row halves too. Some shoppers memorise the 10% step (move the decimal one place) and build the rest from it.

Why two discounts do not add up

Retailers often advertise a sale discount plus an extra coupon. The second percentage is applied to the already reduced price, not to the original. So 20% off followed by 10% off is not 30% off.

Multiply the two multipliers: 0.80 × 0.90 = 0.72. The final price is 72% of the list price, which is a total discount of 28%. On ₹2,500 you pay ₹1,800, not ₹1,750.

The order of the two discounts does not change the result, because multiplication is commutative. What does matter is whether the second one applies to the reduced price or to the original list price; read the offer terms to see which.

Finding the original price from a sale price

Sometimes you only see the final price and the discount, and you want to know what the item cost before. Divide the sale price by the multiplier. A shirt now at ₹2,000 after 20% off had a list price of 2000 ÷ 0.80 = ₹2,500.

A frequent mistake is adding 20% to the sale price (2000 × 1.20 = ₹2,400). That is wrong because the 20% was taken from the larger original, not from the smaller final amount. Dividing is the correct inverse.

What a discount does to the seller's margin

A discount is not a small cost. A retailer selling at ₹2,500 with a cost of ₹1,750 earns ₹750, a 30% margin on price. After a 20% discount the price is ₹2,000, the profit is ₹250 and the margin is 12.5%. A 20% price cut has removed two-thirds of the profit per item.

To stay at the same total profit the seller must therefore sell three times as many units. This is why promotions need a break-even check before they are launched; the related tool in this set is for exactly that kind of promotion arithmetic.

Percentage off versus a flat amount off

A sale can be advertised either as a percentage or as a fixed rupee amount, and the better deal depends on the price. A flat ₹300 off is worth 12% on a ₹2,500 item but only 3% on a ₹10,000 item. A 15% discount, on the other hand, gives ₹375 off ₹2,500 and ₹1,500 off ₹10,000.

To compare the two offers on the same item, convert the flat amount to a percentage by dividing it by the list price. If the converted figure is bigger than the advertised percentage, the flat amount is the better deal; otherwise take the percentage.

Working out the discount you were given

When a shop shows the old price and the new price, you can find the percentage reduction yourself. Subtract the new price from the old one and divide by the old price. A jacket marked down from ₹4,000 to ₹3,000 has a ₹1,000 reduction, which is 1000 ÷ 4000 = 25%.

The division is always by the original price, not by the new one. Dividing ₹1,000 by ₹3,000 gives 33%, which is the percentage you would need to add back to restore the old price, not the discount you received. The two numbers are different, which is why a 25% discount and a 33% mark-up are inverses of each other.

Rounding on price tags

Real shelf prices rarely land on a neat result. A 15% discount on ₹1,999 gives ₹1,699.15, which a shop will usually show as ₹1,699 or ₹1,700. Rounding in the shopper's favour or against it can move the effective discount slightly, so compare using the amount you will actually be charged at the till rather than the calculated figure.

Checking an offer before you buy

• Compare the final price, not the headline percentage; a 40% discount on an inflated list price may still cost more than a 15% discount elsewhere.
• Check whether tax is added after the discount. Most retail pricing applies the discount first and then adds tax to the reduced price.
• Look for minimum purchase or maximum discount caps, which turn a headline percentage into a lower effective one.
• Remember delivery and payment fees, which sit outside the discount.

A quick way to compare two offers is to calculate the price per unit or per use after all adjustments. A calculator that handles sale discounts and stacked offers saves you from doing the multiplication on a phone while standing in the shop.