If the number is divisible by , and find .
If is replaced with a digit from the set (0, 1, 2, 3, 4, 5, 6, 7, 8, or 9) at random, what is the probability that will be divisible by 3?
A longevity chain is a sequence of consecutive positive integers, whose digit sums are never a multiple of 9. What is the longest possible length of a longevity chain?
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As ranges over all real values in the interval , how many values of are there such that is an odd integer?
What is the three digit number