I am compiling the BrainBashers world almanac and it now contains quite a few pages. But just how many?

I know that it takes 121 digits to print all of the page numbers in sequence.

So, how many numbered pages does the book have, and how many times does the number 9 appear?

Puzzle Copyright © Kevin Stone

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Answer

There are 65 pages and the number 9 appears six times.

Reasoning

The 65 pages are (with the six 9's highlighted):

1, 2, 3, 4, 5, 6, 7, 8, **9**, 10, 11, 12, 13, 14, 15, 16, 17, 18, 1**9**, 20, 21, 22, 23, 24, 25, 26, 27, 28, 2**9**, 30, 31, 32, 33, 34, 35, 36, 37, 38, 3**9**, 40, 41, 42, 43, 44, 45, 46, 47, 48, 4**9**, 50, 51, 52, 53, 54, 55, 56, 57, 58, 5**9**, 60, 61, 62, 63, 64, 65.

If we remove the spaces we get:

1

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