Question 900906
You are being asked to show that F is a rational number.
It is rational because it is a repeating decimal form.
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How to work it::
F = 1.3481481481481...
Since the repeat starts after the 3, multiply by 10 to get:
10F = 13.481481...
Since the repeat extends to the thousands place, multiply by 1000 to get:
10,000F = 13481.481481...
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You have isolated the infinite repeating portion of F.
Subtract to get:
(10,000-10)F = 13481-13 
9990F = 13468
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F = 13468/9990 (which mean F is rational)
You could reduce this to 
F = 6734/4995
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Cheers,
Stan H.
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