SOLUTION: 852 digits are used to number the pages of a book consecutively from page 1. How many pages are there in the book?

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Question 923508: 852 digits are used to number the pages of a book consecutively from page 1. How many pages are there in the book?
Found 2 solutions by josmiceli, Alan3354:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
1 - 9 = 9 digits
10 - 99 = 90*2 = 180 digits
100 - 999 = 900*3 = 2700 digits
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There are more than +9+%2B+180%2F2+ pages, but there
are less than +9+%2B+180%2F2+%2B+2700%2F3+ pages
---------------------------
I can say:
Let +p+ = number of pages in book
+p+=+9+%2B+180%2F2+%2B+%28%28+825+-+%28+9+%2B+180%2F2+%29+%29%29+%2F+3++
+p+=+99+%2B+%28+825+-+99+%29+%2F+3+
+p+=+99+%2B+726%2F3+
+p+=+99+%2B+242+
+p+=+341+
There are 341 pages
I hope this logic is right -you might want
a 2nd opinion, too


Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
852 digits are used to number the pages of a book consecutively from page 1. How many pages are there in the book?
---------
1 to 9 = 9 digits
10 to 99 = 2*90 = 180 digits
--> 1 to 99 uses 189 digits
----
852 - 189 = 663
3 digits per page --> 663/3 = 221 pages starting at page 100
Page 100 to 320 is 221 pages
--> 320 pages total
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The other tutor's method is good, but 852 got transposed to 825.