An irrational decimal fraction is created by concatenating the positive integers:
0.123456789101112131415161718192021...
It can be seen that the 12th digit of the fractional part is 1.
If dn represents the nth digit of the fractional part,
find the value of the following expression.
d1 × d10 × d100 × d1000 ×
d10000 × d100000 × d1000000
The trick to this solution is finding the nth digit. The key
to that is figuring out which number is represented by each digit so you
need a slightly different process based on that. Once the awkward math is
worked out it's just a quick number crunch.
79,882