Thread: sum of digits?

the sum of all digits in the numbers 34,35,and 36 is 24 because (3+4)+(3+5)+(3+6)=24. Find the sum of all digits in the first twenty-five natural numbers:1,2,3,4,5,....,23,24,25

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the sum of all digits in the numbers 34,35,and 36 is 24 because (3+4)+(3+5)+(3+6)=24. Find the sum of all digits in the first twenty-five natural numbers:1,2,3,4,5,....,23,24,25

1 + 2 + 3 = 6
4 + 5 + 6 = 15 = 6
7 + 8 + 9 = 24 = 6

10 + 11 + 12 = (1 + 0) + (1 + 1) + ( 1 + 2) = 6
13 + 14 + 15 = 4 + 5 + 6 = 15 = 6
16 + 17 + 18 = 7 + 8 + 9 = 24 = 6
19 + 20 + 21 = 10 + 2 + 3 = 15 = 6
22 + 23 + 24 = 4 + 5 + 6 = 15 = 6

25 = 7?

my pattern does not look beautiful as it is . . . . your hint?

Thank u!