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1997 AIME Problems
5
5
Part of
1997 AIME Problems
Problems
(1)
Fraction Approximation
Source:
12/20/2005
The number
r
r
r
can be expressed as a four-place decimal
0.
a
b
c
d
,
0.abcd,
0.
ab
c
d
,
where
a
,
b
,
c
,
a, b, c,
a
,
b
,
c
,
and
d
d
d
represent digits, any of which could be zero. It is desired to approximate
r
r
r
by a fraction whose numerator is 1 or 2 and whose denominator is an integer. The closest such fraction to
r
r
r
is
2
7
.
\frac 27.
7
2
ā
.
What is the number of possible values for
r
r
r
?