How many digits are required to number a book containing 260 pages?  Choose one.
A) 784  B) 672  C) 492  D) 372  E) 300

Rationale: "9 pages from 1 to 9 will require 9 digits . 90 pages from 10 to 99 will require 90 * 2 = 180 digits . 260 - ( 90 + 9 ) = 161 pages will require 161 * 3 = 483 digits . the total number of digits is 9 + 180 + 483 = 672 . the answer is b ."
Answer: B