Percentages, Money and Financial Problems
Percentages, Money and Financial Problems applies percentage skills, converting between fractions, decimals and percentages, and calculating increase, decrease and reverse percentages, to real financial contexts such as discounts, VAT, simple interest and best-value comparisons.
Before you start
Make sure you're comfortable with these topics first:
Method
- Convert confidently between fractions, decimals and percentages, using key facts such as 1/2 = 50%, 1/4 = 25%, 1/10 = 10% and 1/8 = 12.5% to find percentages mentally where possible.
- To find a percentage of an amount without a calculator, find 10% by dividing by 10, then build the required percentage up or down by adding, halving or doubling.
- For a percentage increase or decrease, either add or subtract the percentage found, or multiply by a single decimal multiplier, for example a 15% increase multiplies by 1.15 and a 15% decrease multiplies by 0.85.
- For simple interest, use the formula Interest = (Principal x Rate x Time) / 100, remembering that Time is measured in years.
- For reverse percentage problems, where you are given an amount after an increase or decrease and asked to find the original, first identify what percentage the given amount represents of the original 100%, then scale up to find 100%.
- For 'best value' comparisons, convert every option to the same unit, such as price per 100 grams or price per item, before comparing them.
- In multi-step financial word problems, work out exactly what is being asked, complete the calculations in a sensible order, and label each amount clearly with its unit (pounds, pence or percentage) as you go.
- Check that your final answer makes sense in context: a sale price should be lower than the original price, and interest earned should be a sensible fraction of the amount saved.
Worked example
A meal at a restaurant costs 45 pounds before charges. A 20% service charge is added to the bill, and then a 10% discount voucher is applied to the new total. Calculate the final price paid.
- Find the service charge: 20% of 45 pounds = 45 x 0.2 = 9 pounds.
- Add the service charge to the original cost: 45 + 9 = 54 pounds.
- Find 10% of this new total: 54 x 0.1 = 5.40 pounds.
- Subtract the discount from the new total: 54 - 5.40 = 48.60 pounds. Final answer: the final price paid is 48.60 pounds.
Practice questions
Type your answer and press Check to be marked straight away, or reveal the answer and mark yourself.
Q1Write 3/8 as a percentage.Show answer
Answer: 37.5% (3 / 8 = 0.375, then multiply by 100)
Q2Find 35% of 160 pounds.Show answer
Answer: 56 pounds (10% = 16 pounds, so 30% = 48 pounds; 5% = 8 pounds; 48 + 8 = 56 pounds)
Q3A jacket priced at 84 pounds is increased by 25% for the winter season. Calculate the new price.Show answer
Answer: 105 pounds (25% of 84 = 21 pounds, then 84 + 21 = 105 pounds)
Q4Calculate the simple interest earned on 600 pounds saved for 3 years at an annual rate of 4%.Show answer
Answer: 72 pounds (Interest = (600 x 4 x 3) / 100 = 7200 / 100 = 72 pounds)
Q5A laptop is on sale for 340 pounds after a 15% reduction. Calculate its original price.Show answer
Answer: 400 pounds (340 pounds represents 85% of the original price, so 1% = 340 / 85 = 4 pounds, and 100% = 400 pounds)
Q6A 750 gram box of cereal costs 2.40 pounds, and a 500 gram box of the same cereal costs 1.70 pounds. Which box offers better value for money? Show your working.Show answer
Answer: The 750 gram box (750 g costs 0.32 pounds per 100 g; 500 g costs 0.34 pounds per 100 g, so the 750 g box is cheaper per 100 g)
Q7Fatima earns 1800 pounds a month and saves 12% of her earnings. Calculate how much she saves each month.Show answer
Answer: 216 pounds (10% of 1800 = 180 pounds; 2% = 36 pounds; 180 + 36 = 216 pounds)
Q8A meal out costs 68 pounds before a 12.5% service charge is added. Calculate the total cost including the service charge.Show answer
Answer: 76.50 pounds (12.5% = 1/8, and 68 / 8 = 8.50 pounds; then 68 + 8.50 = 76.50 pounds)
Exam-style questions
Written in the style of a 13+ Common Entrance exam paper, with a full mark scheme.
A bicycle originally costs 320 pounds. It is reduced by 20% in a spring sale, and then reduced by a further 5% of the new sale price for a loyalty card holder. Calculate the final price paid by a loyalty card holder.
Show mark scheme
Tick each line you got. Your score builds from the marks on the scheme.
Nothing ticked yet - 3 available
Jamie invests 950 pounds in a savings account paying simple interest at 3.5% per year. (a) Calculate the interest earned after 2 years. (b) Calculate the total amount in the account after 2 years.
Show mark scheme
Tick each line you got. Your score builds from the marks on the scheme.
Nothing ticked yet - 4 available
A cafe's takings increased by 8% this year compared with last year, to reach 24732 pounds. (a) Calculate last year's takings. (b) The cafe's costs last year were 60% of last year's takings. Calculate last year's costs.
Show mark scheme
Tick each line you got. Your score builds from the marks on the scheme.
Nothing ticked yet - 5 available
Free printable worksheet
Want more practice on paper? Download the percentages, money and financial problems worksheet pack - 11 pages of exam-style questions with a full mark scheme. One email opens every download in this browser for 14 days - no account, no card. Print it for personal and classroom use.
This topic is chapter 11 of 13+ Maths Workbook, the whole course as one free printable PDF.
Next topics
Not quite what you needed?
Tell us what is missing on percentages, money and financial problems, or which topic to write up next. Every request is read, and we reply to every one.
Build a full practice pack.
This topic is one of hundreds in the library - pick the ones a student needs and generate a printable PDF in minutes.