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Question 242969: The total number of digits it takes to number the pages of a book from
1 to 250 inclusive is:
a.637 b. 638 c. 640 d. 644 e. None
Answer by oberobic(2304)   (Show Source):
You can put this solution on YOUR website! For pages 1-9, there are 9 pages (1 more than 9-1 because you have to count both ends. It takes 1 digit each = 9.
For pages 10-99, there are 90 pages. Similar to the first few pages, this is 1 more than 99-10. We could arrive at this page count by adding 90 to 9, too. At 2 digits each = 90*2 = 180.
So far we've counted up 99 pages. Since there are 250 pages in total, there must be 151 more pages to number. It takes 3 digits each = 151*3 = 453.
Total = 9 + 180 + 453 = 642
That is not one of the options given, so the answer is NONE.
Always check your work, so in this case check whether the total pages = 250.
9 + 90 + 151 = 250.
Ok.
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