Problem:
Let , where the digits are obtained by writing the integers through in order. The digit to the right of the decimal point is
Answer Choices:
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Solution:
Look at the first digits, letting denote the digit. We may break this string of digits into three segments:
There are digits in in , hence in . Dividing by we get with remainder . Thus consists of the first -digit integers. Since the first -digit integer is (not or ), the -digit integer is . Thus .