Question

A printer numbers the pages of a book starting with 1 and uses 3189 digits in all. how many pages does the book have? solve

Answer 1

single digi no. total no=9
remain=3180
from 10 to99 page
total digit used=90×2=180
remain=3000
from 100to999
total digit used =900×3=2700
remain=300
total 4 digit no. possible=300/4=75
total page= 999+75=1074

Answer 2

Given:

A book starts with page 1.

It uses 3189 digits in the book.

To FInd:

The number of pages in the book

Solution:

Number of digits used in the 1-digit pages:

1-digit pages = Page 1 to Page 9

Number of pages = 9

Number of digit used = Number of pages x Number of digits per page

Number of digits used = 9 x 1

Number of digits used = 9

Number of digits used in the 2-digit pages:

2-digit pages = Page 10 to Page 99

Number of pages = 90

Number of digit used = Number of pages x Number of digits per page

Number of digits used = 90 x 2

Number of digits used  = 180

Number of digits used in the 3-digit pages:

3-digit pages = Page 100 to Page 999

Number of pages = 900

Number of digit used = Number of pages x Number of digits per page

Number of digits used = 900 x 3

Number of digits used  = 2700

Number of digits left:

Number of digits left = 3189 - 9 - 180 - 2700

Number of digits left = 300

Number of digits used in the 4-digit pages:

Number of pages = 300 ÷ 4

Number of pages = 75

Find the number of pages used:

Total number of pages = 9 + 90 + 900 + 75

Total number of pages = 1074

Answer: The book has 1074 pages.