Least number to add — Number System Aptitude Question
Least number to add: What is the least number that must be added to 1056 so that the sum is exactly divisible by 23? Answer and worked solution on CodeKairo.
- Topic: Number System
- Section: Quantitative Aptitude
- Difficulty: Easy
- Time target: 45 seconds
Question
What is the least number that must be added to 1056 so that the sum is exactly divisible by 23?
Options
- 2
- 3
- 18
- 21
Show the answer and the worked solution
Correct answer: A. 2
Worked solution
- 1056 ÷ 23 = 45 remainder 21.
- To reach the next multiple, add 23 − 21 = 2.
- Check: 1058 = 23 × 46. ✓
Answer: 2.
The idea
To add: divisor − remainder. To subtract: the remainder itself. Confusing the two is the whole point of offering 21 alongside 2.
Shortcut. Jump to a round multiple: 23 × 50 = 1150, less 23 × 4 = 92, is 1058 — just 2 above 1056.
Common trap. 21 — the remainder of 1056 ÷ 23, which is what must be subtracted (1035 = 23 × 45), not added.