Last reviewed: 7 November 2026
Updated November 2026. These Grade 7 profit, loss, discount and commission notes explain everyday money calculations. Profit = selling price − buying price, and percentage profit = (profit ÷ buying price) × 100%. Discount is a reduction from the marked price, and percentage discount = (discount ÷ marked price) × 100%. Commission is a payment calculated as a percentage of sales.
All prices here are made-up examples and the questions are original practice, not an official paper. For the other Grade 7 maths topics, see our Grade 7 mathematics revision guide and the Grade 7 notes hub.
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What the Grade 7 Curriculum Covers
Money is a sub-strand under Measurements in the Kenya Institute of Curriculum Development’s Grade 7 Mathematics design. It covers profit and loss, percentage profit and loss, discount and percentage discount, commission, interpreting and preparing bills, postal charges, and mobile money services. The design is listed on the KICD Grade Seven curriculum designs page. This page covers profit, loss, discount, commission and bills; for postal and mobile money charges, always use the provider’s current published rates rather than figures from a book, because they change.
Profit and Loss
- If selling price > buying price: profit = selling price − buying price.
- If selling price < buying price: loss = buying price − selling price.
- Percentage profit or loss is calculated on the buying price (cost price).
This percentage method follows OpenStax Prealgebra’s section on applications of percent.
Worked example: profit
A mama mboga buys a crate of tomatoes for KSh 800 and sells them all for KSh 1,000. Profit = 200. Percentage profit = 200 ÷ 800 × 100% = 25%.
Worked example: loss
A trader buys a radio for KSh 1,200 and sells it for KSh 900. Loss = 300. Percentage loss = 300 ÷ 1,200 × 100% = 25%.
Worked example: finding the selling price
A shopkeeper wants a 20% profit on an item bought for KSh 450. Selling price = 450 × 120% = 450 × 1.2 = KSh 540.
Discount
A discount is a reduction from the marked price. Percentage discount is calculated on the marked price, as in OpenStax Contemporary Mathematics’ section on discounts.
Worked example
Shoes marked KSh 2,500 are sold for KSh 2,000. Discount = 500. Percentage discount = 500 ÷ 2,500 × 100% = 20%.
Worked example: price after discount
A school bag marked KSh 1,800 is offered at 15% discount. Discount = 0.15 × 1,800 = 270. Price paid = 1,800 − 270 = KSh 1,530.
Commission
Agents and salespeople are often paid commission: a percentage of the value of what they sell.
Worked example
A sales agent earns 5% commission. In one month she sells goods worth KSh 60,000. Commission = 0.05 × 60,000 = KSh 3,000. If she also has a basic salary of KSh 15,000, her total pay is KSh 18,000.
Worked example: finding the rate
An agent earns KSh 4,200 commission on sales of KSh 84,000. Rate = 4,200 ÷ 84,000 × 100% = 5%.
Interpreting and Preparing Bills
A bill lists each item, its quantity, its unit price and the total. Always check that each line total = quantity × unit price and that the grand total adds up.
| Item | Quantity | Unit price (KSh) | Total (KSh) |
|---|---|---|---|
| Exercise books | 6 | 45 | 270 |
| Pens | 4 | 20 | 80 |
| Geometry set | 1 | 250 | 250 |
| Total | 600 | ||
Original Practice Questions With Worked Answers
- A bicycle bought for KSh 6,000 is sold for KSh 7,200. Find the percentage profit. 1,200 ÷ 6,000 × 100% = 20%.
- A phone bought at KSh 10,000 is sold at a 12% loss. Find the selling price. 10,000 × 0.88 = KSh 8,800.
- A dress marked KSh 3,000 is sold at KSh 2,550. Find the percentage discount. 450 ÷ 3,000 × 100% = 15%.
- Find 3% commission on sales of KSh 150,000. KSh 4,500.
- A bill shows 3 kg of sugar at KSh 160 per kg and 2 packets of flour at KSh 190. Find the total. 480 + 380 = KSh 860.
Cover the answers and attempt each question first. For timed practice, use the Grade 7 revision papers or the Grade 7 CBC Challenge. These notes are free; full revision access is available with the KSh 20 Day Pass or the KSh 500 Monthly Pass.
Frequently Asked Questions
How do you calculate percentage profit?
Divide the profit by the buying price and multiply by 100%.
Is percentage discount calculated on the marked price or the selling price?
On the marked price.
What is commission?
Money paid to an agent or salesperson as a percentage of the value of the goods or services they sell.
What is the difference between profit and discount?
Profit is what a seller gains above the buying price. Discount is a reduction the seller gives from the marked price.