CSATNumber System & SeriesDigits Arithmetic2025

What is the 489th digit in the number 123456789101112...?

Correct Answer: Option D

Explanation

1. **Identify the Benchmarks:** From our study of 'Range Segmentation' [28], we know: - Numbers 1 to 9 (1 digit each) = $9$ digits. - Numbers 10 to 99 (2 digits each) = $90 \times 2 = 180$ digits. - **Total digit

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