Sum of digits? No Calculator Needed.
Number Theory
Level
3
Compute the sum of digits in the following difference:
The answer is 4038.
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1 solution
D = Number of 5s = 2018 5 5 5 5 5 ⋯ 5 5 5 5 5 6 2 − Number of 4s =2018 4 4 4 4 4 ⋯ 4 4 4 4 4 5 2 = ( Number of 5s = 2018 5 5 5 5 5 ⋯ 5 5 5 5 5 6 − Number of 4s =2018 4 4 4 4 4 ⋯ 4 4 4 4 4 5 ) ( Number of 5s = 2018 5 5 5 5 5 ⋯ 5 5 5 5 5 6 + Number of 4s =2018 4 4 4 4 4 ⋯ 4 4 4 4 4 5 ) = Number of 1s = 2019 1 1 1 1 1 ⋯ 1 1 1 1 1 × 1 Number of 0s =2018 0 0 0 0 0 ⋯ 0 0 0 0 0 1 = Number of 1s = 4038 1 1 1 1 1 ⋯ 1 1 1 1 1
Therefore the sum of digits of D is 4 0 3 8 .