Write the multiplier for a 40% increase, then use it to work out the new value of 50 after the increase.
(2)
11
Write the multiplier for a 30% decrease, then use it to find the new value of 90 after the decrease.
(2)
12
A price of 60 pounds is increased by 15%. Calculate the new price.
(2)
13
A price of 220 pounds is decreased by 5%. Calculate the new price.
(2)
14
Work out 12% of 550.
(2)
15
A washing machine costs 320 pounds. In a sale it is reduced by 15%. Calculate the sale price.
(3)
16
A laptop's price increases from 400 pounds to 460 pounds. Work out the percentage increase.
(3)
17
A shop increases all its prices by 8%. A jacket now costs 108 pounds after the increase. Work out the original price before the increase.
(3)
18
A gym membership costs 80 pounds. The fee is first reduced by 20% in a promotion, then the reduced fee is increased by 25% the following year. Work out the fee after both changes.
(3)
19
A phone was originally priced at 250 pounds. It is now on sale for 212.50 pounds. Work out the percentage decrease.
(3)
20
A charity collected 4,500 pounds last year. This year it collected 5,220 pounds. Work out the percentage increase in the amount collected.
(3)
Mark scheme · KS3.M-N11D Percentages of Amounts and Percentage Change: Fluency and Exam Drill
Question 1
B1 25 cao
Answer: 25
Question 2
B1 18 cao
Answer: 18
Question 3
B1 42 cao
Answer: 42
Question 4
B1 40 cao
Answer: 40
Question 5
B1 15 cao
Answer: 15
Question 6
B1 7 cao
Answer: 7
Question 7
M1 correct method to find 10% of 80, e.g. 80 x 0.1 = 8, or multiplier 1.1 used
A1 88 cao
Answer: 88
Question 8
M1 correct method to find 20% of 150 or multiplier 0.8 used
A1 120 cao
Answer: 120
Question 9
M1 correct method, e.g. 10% = 20 and 5% = 10, combined to find 35%
A1 70 cao
Answer: 70
Question 10
M1 correct multiplier 1.4 stated
A1 70 cao
Answer: 70
Question 11
M1 correct multiplier 0.7 stated
A1 63 cao
Answer: 63
Question 12
M1 correct method to find 15% of 60, e.g. 10% = 6, 5% = 3, combined = 9
A1 69 pounds cao
Answer: 69 pounds
Question 13
M1 correct method to find 5% of 220, e.g. 10% = 22, halved to 11
A1 209 pounds cao
Answer: 209 pounds
Question 14
M1 correct method, e.g. 10% = 55 and 2% = 11, combined to find 12%
A1 66 cao
Answer: 66
Question 15
M1 correct method to find 15% of 320, e.g. 10% = 32, 5% = 16
M1 correct subtraction of the reduction from 320
A1 272 pounds cao
Answer: 272 pounds
Question 16
M1 finds the increase, 460 - 400 = 60
M1 divides the increase by the original price, 60 / 400
A1 15% cao
Answer: 15%
Question 17
M1 recognises the multiplier for an 8% increase is 1.08
M1 divides the new price by the multiplier, 108 / 1.08
A1 100 pounds cao
Answer: 100 pounds
Question 18
M1 correct method for the 20% reduction, e.g. 80 x 0.8 = 64
M1 correct method for the 25% increase applied to 64, e.g. 64 x 1.25 = 80
A1 80 pounds cao
Answer: 80 pounds
Question 19
M1 finds the decrease, 250 - 212.50 = 37.50
M1 divides the decrease by the original price, 37.50 / 250
A1 15% cao
Answer: 15%
Question 20
M1 finds the increase, 5,220 - 4,500 = 720
M1 divides the increase by the original amount, 720 / 4,500