Oh no! How many pages???
Number Theory
Level
2
Anna used 189 digits to number the pages in her diary.
How many pages does the diary have?
The answer is 99.
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That was a tough one!
Anna used 9 digits to number the pages 1 – 9.
She used 90 x 2 = 180 digits to number the pages 10 – 99.
She used 189 digits to number 99 pages.