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Shops and other business will offer discounts to tempt buyers.

The discount may be offered as a percentage, fraction, fixed amount or a multi-buy option.

Example 1

A shop normally sells large bars of chocolate at £1.20 each. It is currently selling the bars at `frac(1)(4)` off the original price, or buy three for the price of two.

Which is the better option for buying three bars?

Note that working is given in the answer to justify the decision.


Three for the price of two.

Three for the price of two is 2 x £1.20 = £2.40.

`frac(1)(4) xx £3.60` = 90p. Subtract from £3.60 to get £2.70.

Example 2

A shop was selling a phone contract for an initial cost £50.00, plus £24.00 per month for a further 12 months. In a sale, it sold the contract without an initial cost.

What was the overall percentage decrease in the price? Give your answer to two significant figures.

Original cost £50 + 24 x 12 = £338

The new cost reduces it by £50

`frac(50)(338) = 0.1479`

Multiply by 100 for 14.79% = 15% (2sf)

Answer: 15%

See also Percentage Increase and Decrease