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# Percentages (Medium)

Don't forget, per cent means per hundred, e.g. 10% = 10100. Suppose you were asked to find 10% of 50, how would you do it? This is how you would do it: 10100 × 50 = (10 × 50) ÷ 100 = 5. It's as simple as that!

There are various ways to write numbers such as decimals, fractions or percentages. If I picked a bunch of flowers from the garden with 9 purple flowers and 3 yellow, what percentage of yellow flowers do I have? 3 out of 12 is one-quarter which can be written as either 0.25, 14 or 25%.

This is the first of our medium 11-plus Maths quizzes on percentages. In this quiz you'll get some practice in working out percentages with various numbers. Make sure you play this one first before moving onto the next quiz.

1.
What is 60% of 250?
0.15
1.5
150
15
60% of 250 = 60100 × 250 = (60 × 250) ÷ 100 = 150. DON'T forget: when you divide by 100, move the decimal point two places to the left
2.
If 70% of the population of a country of 60,000,000 have mobile phones, what percentage don't have mobile phones?
42%
30%
18%
60%
100% - 70% = 30%. The sum of the various percentages MUST add to 100%
3.
What is 5.5% of 100?
5.5
55
0.55
0.055
5.5% of 100 = 5.5100 × 100 = (5.5 × 100) ÷ 100 = 5.5. You shouldn't have had to calculate anything in this question because X% of 100 = X for all values of X
4.
What is 25% of 75?
0.1875
1.875
187.5
18.75
25% of 75 = 25100 × 75 = (25 × 75) ÷ 100 = 18.75. DON'T forget: when you divide by 100, move the decimal point two places to the left
5.
Henry is paid £42,400 per annum (per year). If he gets a 3.4% pay increase, how much will he earn now per annum?
£43,841.60
£42,841.60
£40,958.40
£1,441.60
3.4% of £42,400 = 3.4100 × 42,400 = (3.4 × 42,400) ÷ 100 = £1,441.60 BUT this is only the interest. He will now earn £42,400 + £1,441.60 = £43,841.60
6.
If John loses 25% of £900, how much does he lose?
£0.225
£2.25
£22.50
£225.00
25% of £90 = 25100 × 900 = (25 × 900) ÷ 100 = £225
7.
Peter will earn 3.2% interest on £12,500. How much money will he earn in interest?
£40.00
£4.00
£400
£4,000
3.2% of £12,500 = 3.2100 × 12,500 = (3.2 × 12,500) ÷ 100 = £400
8.
What is 20% of 20% of 500?
100
20
200
2
20% of 500 = 20100 × 500 = (20 × 500) ÷ 100 = 100 AND 20% of 100 = 20100 × 100 = (20 × 100) ÷ 100 = 20. NOTE: 20% of 20% is NOT equal to 40%. The word 'OF' means multiply!
9.
What is 40% of 18?
0.0072
0.72
72
7.2
40% of 18 = 40100 × 18 = (40 × 18) ÷ 100 = 7.2
10.
What is 62.5% of 12?
75
7.5
0.75
0.075
62.5% of 12 = 62.5100 × 12 = (62.5 × 12) ÷ 100 = 7.5
Author:  Frank Evans