IMO Practice Test — Statistics
6 Questions • 25 min • Olympiad level
25:00
Question 1 of 6
hard
Data set: 5,7,9,11,13,15,17,19,21,23,25. Find Q1, Q3
9,19
9,21
11,19
7,23
Explanation: Median=15, lower half:5-13, Q1=9, upper half:17-25, Q3=19
Question 2 of 6
hard
Mean of 4 numbers is 8. Three numbers: 5,7,10. Find 4th
6
8
10
12
Explanation: Total=32, 5+7+10=22, 4th=10
Question 3 of 6
hard
A box plot has min=10, Q1=20, median=35, Q3=50, max=80. IQR?
15
20
30
45
Explanation: IQR=Q3-Q1=50-20=30
Question 4 of 6
hard
Histogram shows intervals 0-9(5),10-19(12),20-29(8),30-39(3). Total data?
28
30
25
32
Explanation: 5+12+8+3=28
Question 5 of 6
hard
Add a number to 3,5,7,9 to make mean=7. What number?
9
10
11
12
Explanation: Current sum=24, need 5 numbers sum to 35, add 11
Question 6 of 6
hard
Data: 2,3,5,5,7,8,9,11. Which measure changes most if 11 replaced with 30?
Mean
Median
Mode
Range
Explanation: Range changes from 9 to 28 (largest change)