Discussion
All the natural numbers from 259 to 492 are written down side by side, giving the very large number 259260261…491492. How many 8s are used in writing it?
Answer: D
Count the 8s by the place they occupy.
Units digit 8 - the numbers 268, 278, …, 488:
\[ \frac{488 - 268}{10} + 1 = 23 \]
Tens digit 8 - the blocks 280–289, 380–389 and 480–489:
\[ 3 \times 10 = 30 \]
No number in the range has 8 in the hundreds place, since the hundreds digits are only 2, 3 and 4.
\[ 23 + 30 = 53 \]
288 and 388 and 488 are each counted twice - once for each 8 - which is correct, since the question asks how many 8s are written.
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