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1989 AIME Problems
3
3
Part of
1989 AIME Problems
Problems
(1)
Decimal Fun
Source:
2/19/2006
Suppose
n
n
n
is a positive integer and
d
d
d
is a single digit in base 10. Find
n
n
n
if
n
810
=
0.
d
25
d
25
d
25
…
\frac{n}{810}=0.d25d25d25\ldots
810
n
=
0.
d
25
d
25
d
25
…
geometric series