Answer:
20
Explanation:
The given relation can be written as the 2-step linear equation ...
(1/3)n +2 1/3 = 9
n +7 = 27 . . . . . . . . . step 1: multipy by 3 (makes the coefficient = 1)
n = 20 . . . . . . . . . . . step 2: subtract 7 (separates variable from constant)
The number is 20.
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Additional comment
Usually it is convenient to do the two steps in the opposite order: get the variable term by itself, then make its coefficient 1. Here, we chose the order we did because it eliminated fractions from the problem, which is often a step you'd like to do first.