The answer is: 1/6 ft.
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Step-by-step explanation:
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25 inches : 25 ft:: (1/6) inch: x (ft). 
So: 25/25 = (1/6) / x ; solve for "x" ;
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 Note: the "25/25" cancel to '1", so we have: 
1 = (1/6) / x ;
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(1/6) ÷ x = 1 ;
 1*x = x = 1/6.
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The answer is: 1/6 ft.
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