Question

What is the total number of digits required in numbering the pages of a book, which has 1,150 pages?

Answer 1

3493

Explanation:

Pages 1 through 9:

There are 9 pages using 1 digit each.

9 * 1 = 9

Pages 10 through 99:

There are 90 pages using 2 digits each:

90 * 2 = 180

Pages 100 through 999:

There are 900 pages using 3 digits each:

900 * 3 = 2700

Pages 1000 through 1150:

There are 151 pages using 4 digits each.

151 * 4 = 604

Total number of digits:

9 + 180 + 2700 + 604 = 3493

Answer: 3493