IMO Practice Test — Percentages
6 Questions • 25 min • Olympiad level
25:00
Question 1 of 6
medium
If 40% of a class are boys, what percent are girls?
40%
60%
100%
50%
Explanation: 100% − 40% = 60%.
Question 2 of 6
hard
2/5 as a percentage is…
25%
40%
45%
52%
Explanation: 2/5 = 40/100 = 40%.
Question 3 of 6
medium
60% of 50 = ?
25
30
35
60
Explanation: 10% of 50 = 5, × 6 = 30.
Question 4 of 6
hard
Which set are all equal?
1/2, 0.5, 50%
1/4, 0.4, 40%
1/5, 0.5, 5%
3/4, 0.34, 34%
Explanation: 1/2 = 0.5 = 50%.
Question 5 of 6
hard
20 out of 50 marks. What percent is that?
20%
40%
50%
70%
Explanation: 20/50 = 40/100 = 40%.
Question 6 of 6
hard
A class of 40 has 25% absent. How many are present?
10
30
25
15
Explanation: 25% of 40 = 10 absent, so 40 − 10 = 30 present.