Question

What is the sum of all digits in the sequence 1,2,3,4... 98,99,100? (For example, the sum of digits in 34 and 35 is 3+4+3+5=15)

Answer 1

Explanation:

To find the sum of all the digits in the sequence 1, 2, 3, ..., 98, 99, 100, we can use a bit of arithmetic.

First, let's find the sum of the digits in the first 99 numbers of the sequence. Each number in the sequence has two digits, so the sum of the digits in the first 99 numbers is 99 * 18 = 1872.

Next, we need to add in the digits in the number 100. The sum of the digits in 100 is 1 + 0 + 0 = 1.

Therefore, the sum of all the digits in the sequence 1, 2, 3, ..., 98, 99, 100 is 1872 + 1 = 1873.