[tex]\red{B. \: 13/14}[/tex]
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Since, the numerator and denominator are consecutive numbers, it's already on lowest term.
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There's 2 things you should know if the fraction is already on lowest term
-If the numerator and denominator are consecutive numbers
For example: 1/2, 3/4, 6/7
-If the numerator and denominator has no common factors aside from 1
For example : 4/9, 11/14, 5/7
