Number theoryDifficulty 2.4JuniorFind the answerNetherlands
Farida makes a list of the integers between 1 and 10,000 that are divisible by 7. For every number on the list she adds the digits of the number. What is the smallest number that occurs as an outcome? A) 1 B) 2 C) 3 D) 4 E) 5
This was a multiple-choice question, but the options didn't survive into the
source we have. The answer given is B, and the solution
below works it through.
Solution
B) 2
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Source: MathNet,
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