Question

What is the total number of digits required in numbering the pages of a book, which has 1,724 pages?

Answer 1

5,789 digits

Explanation:

1 digit numbering from page 1-9

That is 9 pages×1 digit=9 digits

2 digit numbering from page 10 to 99

That is 90 pages × 2 digits=180 digits

3 digit numbering from page 100 to 999

That is 900 pages× 3 digits=2,700 digits

4 digits numbering from page 1000 to 1,724

That is 725 pages × 4 digits

=2,900 digits

Total digits=9 digits+ 180 digits+2,700 digits+2,900 digits

=5,789 digits

Answer 2

5789 digits

Explanation:

Given that the number of pages ares: 1,724

As we know that:

• (from 1 - 9) there are 9 one-digit numbers
• (from 10- 99) there are 90 two-digit numbers
• (from 100 - 999) there are 900 three-digit numbers
• (from 1,000 - 1,724) there are 725 four-digit numbers

So the total are:

`= 9(1)+90(2)+900(3)+725(4)\\\\= 9+180+2,700+2,900\\\\= 5,789\ digits`