2893 digits in all, made up as follows: 9 1-digit numbers (1 to 9) = 1*9 = 9 digits 90 2-digit numbers (10 to 99) = 2*90 = 180 digits 900 3-digit numbers (100 to 999) = 3*900 = 270 digit 1 4-digit number (1000) = 4*1 = 4 digits
2
There are 9 possible numbers for the first digit (one of {1, 2, ..., 9}); with 9 possible digits for the second digit (one of {0, 1, 2, ..., 9} which is not the first digit)); with 8 possible digits for the third digit (one of {0, 1, 2, ..., 9} less the 2 digits already chosen); This there are 9 × 9 × 8 = 648 such numbers.
6
Any number that has 4 or 5 digits. A digit in a number is one number place. 1 has 1 digit, 11 has 2 digits, 111 has 3 digits, and so on.
In the numbers 1-9 each number has 1 digit and there are 9 of them, so that's 9.In 10-99 each number has 2 digits, and there are 90 of them: 2x90 = 180There are 900 three digit numbers [100 through 999]: 2700 digits.There are 9000 four digit numbers: 36000 digits.90,000 numbers with five digits: 450,000 digits.900,000 numbers with six digits: 5,400,000 digits.Then 1 number with seven digits: 7 digits.Add them up and you have 5,888,896 digits.
There are 34 = 81 numbers.
162
First 9 pages = 9 digit. That leaves 142 digits. @ 2 digit per page, that is 142/2 = 71 pages with 2-digit numbers. So, 9 pages with 1-digit numbers + 71 pages with 2-digit numbers = 80 pages.
1
6!
256 numbers.