6. When Xiaopang was compiling the page numbers for a book, he used a total of 1101 digits. It is known that the page numbers are consecutive natural numbers starting from 1. How many pages does this book have?
【Analysis】First, estimate, 1 to 99 has 189 digits, so the three-digit numbers have $(1101-189) \div 3=304$ (numbers), then this book has a total of $99+304=403$ (pages).