Well done, you scored out of 10. As a reward for completing the quiz, meet Harry, Hermione, Ron, Genny, Luna and Neville, one of our favourite pets!
Bad Luck, you only scored out of 10. But as a reward for completing the quiz, meet Harry, Hermione, Ron, Genny, Luna and Neville, one of our favourite pets!
Level 7-8 Numbers - Percentages - Increases and Decreases
A beehive increases by 7% a day.
Level 7-8 Numbers - Percentages - Increases and Decreases
Percentages help compare changes. Learn to increase or decrease amounts, find multipliers, and reverse percent changes in realistic KS3 money and measure problems.
Explore the Topic →
(quiz starts below)
Fascinating Fact:
Inflation uses percentage increases to show how prices change over time. A 3 percent annual rise adds £3 to every £100 spent.
In KS3 Maths, you’ll calculate percentage increases and decreases using multipliers, compare discounts, and solve reverse-percentage problems. Expect money, measures, and data contexts where clear working and sensible rounding matter.
Key Terms
Percentage change: How much a value increases or decreases compared with the original, expressed per 100.
Multiplier: A single number to apply a percentage change, e.g., increase by 12% → multiply by 1.12; decrease by 12% → multiply by 0.88.
Reverse percentage: Finding the original amount by dividing the final amount by the multiplier used.
Frequently Asked Questions (Click to see answers)
How do I increase a number by a percentage?
Use a multiplier of 1 + (percentage/100). Example: increase £240 by 15% → £240 × 1.15 = £276.
How do I decrease a number by a percentage?
Use a multiplier of 1 − (percentage/100). Example: decrease £80 by 25% → £80 × 0.75 = £60.
How do I find the original price before a percentage change?
Divide by the multiplier. Example: £45 after 10% off means original = £45 ÷ 0.90 = £50.
A beehive increases by 7% a day. Initially there are 1,250 bees. How many will there be after a week?
1,620
1,800
2,000
2,007
A calculator is helpful for this kind of calculation! This problem is an example of compound increase. Problems like this can be solved using the compound interest formula:
M = P( 1 + i )n
Here, M = the final number of bees; P = the initial number of bees; i = the percentage increase (if it is a decrease, it will be negative; n = the number of days (but it could be weeks/months/years or any time period, depending on the problem) and it is the POWER to which (1 + i) has to be raised. Plug in the numbers and do the calculation
2 .
Barbara bought a box of 35 pens for £40.25. She sold all the pens for £1.70 each. What was her percentage profit?
39.4%
40.7%
45.8%
47.8%
Not a bad little earner!
3 .
Due to severe weather, a polar bear colony goes from 328 bears to 246. What percentage decrease is this?
20%
22%
25%
26%
Remember, the change is always compared with the original value
4 .
Michelle bought a caravan for £13,500 and sold it two years later for £11,200. What is the percentage loss?
M = P( 1 + i )n
Here, M = the final number of bees; P = the initial number of bees; i = the percentage increase (if it is a decrease, it will be negative; n = the number of days (but it could be weeks/months/years or any time period, depending on the problem) and it is the POWER to which (1 + i) has to be raised. Plug in the numbers and do the calculation