This study notes covers Worked Examples within Percentage Problems for GCSE Mathematics. Revise Percentage Problems in Number for GCSE Mathematics with 14 exam-style questions and 22 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 5 of 7 in this topic. Use this study notes to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 5 of 7
Practice
14 questions
Recall
22 flashcards
Worked Examples
Example 1: VAT Calculation
Problem: A computer costs £450 before VAT. VAT is charged at 20%. What is the total cost?
Solution:
Method 1 (Two steps): VAT = £450 × 20/100 = £90, Total = £450 + £90 = £540
Method 2 (Multiplier): Total = £450 × 1.2 = £540
Answer: £540
Example 2: Simple Interest
Problem: £2500 is invested at 4.5% simple interest per year. How much interest is earned in 3 years?
Solution:
Using I = PRT/100
I = (£2500 × 4.5 × 3) ÷ 100 = £33,750 ÷ 100 = £337.50
Answer: £337.50 interest earned
Example 3: Multi-step Discount
Problem: A £120 item has a 15% discount, then a further 10% student discount is applied to the reduced price. What's the final cost?
Solution:
After first discount: £120 × 0.85 = £102
After second discount: £102 × 0.9 = £91.80
Alternative: £120 × 0.85 × 0.9 = £91.80
Answer: £91.80
Example 4: Commission Calculation
Problem: A salesperson earns 6% commission on all sales. In one month, they sell £12,000 worth of products. What commission do they earn?
Solution:
Commission = £12,000 × 6/100 = £12,000 × 0.06 = £720
Answer: £720 commission