Profit Loss and Discount
ICSE Class 8 · Mathematics · Chapter 8
What this chapter covers
- Cost price, selling price, profit and loss
- Profit per cent and loss per cent
- Finding the selling price or the cost price
- Advanced problems on profit and loss
- Overhead expenses
- Marked price and discount
- Discount, profit and loss together
- Tax on goods
Key definitions
Cost price is the amount of money a person pays to buy an article.
Selling price is the amount of money for which a person sells an article.
Profit is the amount by which the selling price of an article is more than its cost price.
Loss is the amount by which the cost price of an article is more than its selling price.
Profit per cent is the profit expressed as a percentage of the cost price.
Loss per cent is the loss expressed as a percentage of the cost price.
Overhead expenses are the extra amounts spent on an article after buying it and before selling it, such as transport, repairs, loading charges or labour.
Marked price is the price printed or written on the label of an article before any reduction is made.
Discount is the reduction allowed by the seller on the marked price of an article.
Discount per cent is the discount expressed as a percentage of the marked price.
Sales tax is a tax charged by the government on the sale of goods, which the seller collects from the buyer along with the price.
Key points
- Profit = SP − CP when SP is more than CP; Loss = CP − SP when CP is more than SP.
- Profit per cent and loss per cent are always calculated on the cost price.
- Taking CP as 100 turns most problems into a simple proportion: SP is 100 + profit% or 100 − loss%.
- To find CP from SP, multiply by 100 and divide by (100 + profit%) or (100 − loss%); never subtract the percentage of SP.
- Overhead expenses such as transport, repairs and labour are added to the purchase price to give the cost price.
- Discount is a reduction on the marked price, and discount per cent is calculated on the marked price.
- SP = MP − Discount; after a discount of d%, SP is (100 - d)% of MP.
- A gain and a loss of the same per cent on two articles sold at the same price always give an overall loss.
- Successive discounts are smaller than their sum, because each later discount is taken on a reduced price.
- Tax on goods is calculated on the selling price after any discount, and the buyer pays SP + tax.