Difficulty: Easy
Correct Answer: 1
Explanation:
Introduction / Context:
This problem tests modular arithmetic and divisibility. We want the smallest non-negative addition to 1057 that makes the sum a multiple of 23. Such questions appear frequently in aptitude tests to assess number sense and comfort with remainders.
Given Data / Assumptions:
Concept / Approach:
If r is the remainder when N is divided by d, then N = q*d + r. The smallest k that makes N + k a multiple of d is k = (d - r) when r != 0, and k = 0 when r = 0. We compute r using N mod d.
Step-by-Step Solution:
Verification / Alternative check:
Direct division shows 23 * 46 = 1058; being one less means we must add 1 to reach the next multiple. This confirms k = 1.
Why Other Options Are Wrong:
2, 3, 4, and 6 overshoot the next multiple; adding any of them does not land exactly on a multiple of 23.
Common Pitfalls:
Confusing remainder 22 with the required addition; remember to add (23 - 22) and not 22 itself.
Final Answer:
1
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