What is the sum of all digits in final result when 

1+11+111+…+11…111+11+111+…+11…11 (1010 digit 11s) 

is computed? 

Answer: The sum of all digits in final result is

Susan writes all the counting numbers, from 11 to 100100, on a piece of paper. She then asks her sister to find the number of all the digits found on the paper. The answer is .....

Susan writes all the counting numbers, from 11 to 100100, on a piece of paper. She then asks her sister to find the number of all the digits found on the paper. The answer is ......?

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The sum of the digits of all 2-digit numbers is .............

The sum of digits of all 2-digit numbers is....................

Given 4 digits: 4, 6, 2, 0. 
What is the difference of the largest and the smallest 4-digit numbers that can be formed from these digits. Use each digit only ones.
Answer: The difference is 

If B is not divisible by 24 and B is the greatest 5 - digit number that the sum of the sum of all digits is 21 then B = ?

If B is not divisibly by 24 and B is the greatest 5 - digit number that the sum of all digits is 21 then B = ................

If B is not divisible by 24 and B is the greatest 5 - digit number  that the sum of all digits is 21 then B= ?