Percentages

Question 1

How much tax would you pay if your Gross Income was £25,000?
(Personal Allowance is £11,500 and rate of tax is 20%?)

Answer 1

£25,000 - £11,500 = £13,500
20% of £13,500 =
13,500 ÷ 100 x 20
= £2,700

Question 2

There are 4 red balls and 9 green balls in a bag.

What percentage of the balls are green?

Answer 2

Write the fraction first!
= 9 ÷ 13 = 0.69230..

0.69230 x 100 = 69.23 (69%).

Question 3

What is the formula for finding a percentage change?

Answer 3

Change in value ÷ Original value x 100%

Question 4

A shop is offering 20% discount today. The price once the discount has been applied is £90. How much was it before the offer?

Answer 4

£90 equates to 80%
Hence 100% = £90 ÷ 0.8
= £112.50
(check: £112.50 x 0.8 = £90)

Question 5

A shop bought a jacket for £50 and sold it for £90. What was the percentage profit?

Answer 5

Profit = sale – cost = £40

% Profit = Profit ÷ Cost x 100%

40 / 50 x 100 = 80%

Question 6

Convert 35% to

a) a fraction in its simplest form
b) a decimal

Answer 6

35% = 35/100 (÷5) = 7/20

35% = 35 ÷ 100 = 0.35

Question 7

If £320 is invested at 15% compound interest p.a. How much will it be worth after 2 years?

Answer 7

1st Year: £320 x 1.15 = £368

2nd Year: £368 x 1.15 = £423.20

Question 8

Find 10% of £54

Answer 8

54 ÷ 10 = £5.40

remember 2 digits after the decimal point for money