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Profit, loss and discounts

Calculate profit and loss as amounts and percentages; find discount amounts and sale prices; solve GST and reverse price problems.

Worked examples

Finding profit and loss

Straightforward

Problem

A trader buys a watch for $35\$35 and sells it for $49\$49. Find the profit.

Expressing profit as a percentage and finding a sale price

Moderate

Problem

A bicycle is bought for $80\$80 and sold for $92\$92. Express the profit as a percentage of the cost price.

Finding the pre-GST price

Challenging

Problem

A laptop has a GST-inclusive price of $880\$880. GST is 10%10\%. Find the pre-GST price.

Practise

Q1·Straightforward
A book has a cost price of $40\$40 and a selling price of $55\$55.

Find the profit.
Q2·Straightforward
A pair of shoes is bought for $80\$80 and sold for $62\$62.

Find the loss.
Q3·Straightforward
A mug costs $4.50\$4.50 to make and is sold for $7.00\$7.00.

Find the profit in dollars.
Q4·Straightforward
A car is bought for $12 000\$12\,000 and sold for $10 500\$10\,500.

Find the loss.
Q5·Moderate
A bicycle is bought for $80\$80 and sold for $100\$100.

Find the profit as a percentage of the cost price.
Q6·Moderate
A tablet is bought for $600\$600 and sold for $510\$510.

Find the loss as a percentage of the cost price.
Q7·Moderate
A jacket has a marked price of $120\$120 and is offered at a 25%25\% discount.

Find the discount amount in dollars.
Q8·Moderate
A shirt has a marked price of $85\$85 and is discounted by 20%20\%.

Find the sale price in dollars.
Q9·Challenging
A phone is sold for $180\$180 at a 20%20\% profit.

Find the cost price.
Q10·Challenging
A price before GST is $95\$95. GST is charged at 10%10\%.

Find the GST-inclusive price in dollars.
Q11·Challenging
A price including GST of 10%10\% is $132\$132.

Find the pre-GST price.
Q12·Challenging
A book is sold for $28\$28 at a 40%40\% profit.

Find the cost price.