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A printer numbers the pages of a book starting with 1. He uses 3189 digits in all. How many pages does the book have?
Given:
A printer numbers the pages of a book starting with 1. He uses 3189 digits in all.
To do:
We have to find the number of pages in the book.
Solution:
Number of pages with one digit$=9$ (1 to 9)
Number of pages with two digits$=99-9=90$ (10 to 99)
Number of pages with three digits$=999-99=900$ (100 to 999)
Let the number of pages with four digits be $x$.
This implies,
$3189=9\times1+90\times2+900\times3+4\times x$
$3189=9+180+2700+4x$
$4x=3189-2889$
$x=\frac{300}{4}$
$x=75$
Total number of pages in the book$=9+90+900+75=1074$.
The total number of pages in the book is 1074.
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