Find the smallest number of five digits which is exactly divisible by 476.
Aptitude
Number System
Difficulty: Medium
Choose an option
-
A10476
-
B10004
-
C10472
-
D10952
Answer
Correct Answer: 10472
Explanation
### Concept & Logic
To find the smallest $N$-digit number divisible by a given divisor, start with the absolute smallest possible $N$-digit base number. Treat it as an addition problem because subtracting anything from the smallest $N$-digit number would reduce it to $N-1$ digits.
### Step-by-Step Solution
- **Given:** Find the smallest 5-digit number divisible by 476.
- **Calculation / Deduction:** The absolute smallest 5-digit number is 10000.
- Divide 10000 by 476 to determine the remainder.
- $10000 \div 476$ yields a quotient of 21 and a remainder of 4.
- Since we cannot subtract (which would yield a 4-digit number like 9996), we must add to reach the next multiple.
- Number to add = $\text{Divisor} - \text{Remainder} = 476 - 4 = 472$.
- Add this value to the base number: $10000 + 472 = 10472$.
### Exam Strategy & Shortcut
Always write down the base number (like 10000) and immediately find the remainder. Apply the standard formula for finding the next multiple: $\text{Base} + (\text{Divisor} - \text{Remainder})$. Never use subtraction for smallest N-digit constraint questions.
### Common Pitfall
Students often subtract the remainder (4) from 10000 to get 9996. While 9996 is perfectly divisible by 476, it is only a 4-digit number, thereby failing the primary constraint of the question.
### Final Answer
Therefore, the correct answer is 10472.