Answer:
2 13/14 feet
Step-by-step explanation:
The remaining length is the difference between the starting length and the amount cut off:
5 3/7 - 2 1/2 = (5 -2) +(3/7 -1/2) = 3 +((3·2-7·1)/(7·2)) = 3 -1/14
= 2 13/14 . . . feet remaining
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Additional comment
Addition and subtraction of fractions can be accomplished using a formula that does not rely on finding a least common denominator. In this case, the denominators have no common factors, so their product is, in fact, the least common denominator.
[tex]\dfrac{a}{b}-\dfrac{c}{d}=\dfrac{ad-bc}{bd}[/tex]
