To number the pages of a dictionary, the digit 1 was printed 1988 times. How many pages does this dictionary have?
Let's observe that:

- every 10 numbers, the digit 1 is printed once in the units place,
- every 100 numbers, the digit 1 is printed 10 times in the tens place,
- every 1000 numbers, the digit 1 is printed 100 times in the hundreds place.

Thus, from 1 to 999, the digit 1 is printed:

100 times in the units place + 100 times in the tens place + 100 times in the hundreds place = 300 times.

From 1000 to 1999, the digit 1 is printed another 300 times in the units, tens, and hundreds places, and 1000 times in the thousands place, so between 1 and 1999, the number of times the digit 1 is printed is: 300 + 300 + 1000 = 1600.

From 2000 to 2999, the digit 1 is printed another 300 times, making the total 1600 + 300 = 1900.

From 3000 to 3099, there are 20 instances of the digit 1, from 3100 to 3119, there are 40 instances of the digit 1, and from 3120 to 3139, there are 22 instances of the digit 1, so up to 3139, the digit 1 is printed: 1900 + 20 + 40 + 22 = 1982 times. Since 6 more instances of the digit 1 are needed, the number of pages in the book is 3144.