Answer:
of a yard
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Step-by-step explanation:
The longest is
yard and the shortest is
of a yard.
This is because 6 is the largest numerator and 1 is the smallest numerator.
Subtract the two fractions:

We subtract the numerators while the denominator stays the same at 6 the entire time.
This is the difference between the longest and shortest ribbon, and the unit is in yards.