Do I simplify fractions in a two column proof

Question

6/7y=3 is the answer y=21/6 or y=3.5?

Answer 1

(6/7)7=3

(7/6)(6/7)(y)=(7/6)(3)

y=21/6=7/2=3.5 (or 3 1/2)

always express an improper fraction as a mixed number in simplest form or as a decimal