Question 1: Calculate the percentage increase from 150 to 180.

Answer: 20

Question 2: A product's price decreases from £50 to £40. What is the percentage decrease?

Answer: 20

Question 3: A school had 300 students last year. This year, the number increased to 330. Find the percentage change in student numbers.

Answer: 10

Question 4: A factory produced 1200 units of a product last month. This month, production was 1080 units. What is the percentage decrease?

Answer: 10

Question 5: A car's value appreciated from £8,000 to £8,400. Calculate the % change in value.

Answer: 5

Question 6: A gym membership fee increased from £30 to £36. Find the percentage increase.

Answer: 20

Question 7: A student scored 45 marks out of 60 in a test. The next time, they scored 54 marks. What is the percentage increase in their score?

Answer: 20

Question 8: A shop sold 80 items last week. This week, sales rose to 96 items. Calculate the percentage change in sales.

Answer: 20

Question 9: Plot the graph of y = 2x for x values from 0 to 10. (Students will draw on grid)

Answer:

Question 10: Construct a triangle with sides measuring 3 cm, 4 cm, and 5 cm. Identify the percentage change if the shortest side increases to 4.5 cm.

Answer: 50

Question 11: A company's revenue increased from £200,000 to £220,000. Calculate the percentage increase. (Note common mistake: using wrong base value)

Answer: 10

Question 12: An error analysis question: A student calculated the percentage increase from 80 to 100 as 25%. Identify the mistake and correct it.

Answer: They divided 20 by 80 instead of 20 by 80 and then multiplied by 100; correct percentage change is 25% but the calculation method was correct, so the student was actually right. (Alternatively, if the student used 100 as base, correction needed.)