IMO Practice Test — Addition & Subtraction (Large Numbers)
6 Questions • 12 min • Olympiad level
12:00
Question 1 of 6
medium
2,500 + 2,500 + 2,500 + 2,500 = ?
7,500
10,000
12,500
9,000
Explanation: Four 2,500s = 10,000.
Question 2 of 6
hard
A town has 12,400 men and 11,890 women. How many people in total?
23,290
24,290
24,390
23,390
Explanation: 12,400 + 11,890 = 24,290.
Question 3 of 6
hard
The sum of the smallest 4-digit number and the largest 3-digit number is…
1,099
1,999
1,000
1,998
Explanation: 1,000 + 999 = 1,999.
Question 4 of 6
hard
A rough estimate of 3,120 + 4,880 is…
about 7,000
about 8,000
about 9,000
about 6,000
Explanation: ≈ 3,000 + 5,000 = 8,000 (exact 8,000).
Question 5 of 6
medium
The exact answer to 499 + 501 is closest to which estimate?
900
1,000
1,100
800
Explanation: ≈ 500 + 500 = 1,000.
Question 6 of 6
hard
A trip is 8,000 m. After walking 3,450 m and 1,550 m, how far is left?
3,000 m
4,000 m
2,000 m
3,500 m
Explanation: 3,450 + 1,550 = 5,000; 8,000 − 5,000 = 3,000 m.