Since you posted this problem in the Pre-Algebra forum, I wonder if your problem is
(2/3)*n = 1
If this is what you meant, then we want to get 1n, or just n, on the left side. Since n has been multiplied by 2/3, we can multiply both sides by 3/2:
(3/2)*(2/3)*n = (3/2)*1
(3/2) and (2/3) are reciprocals; when you multiply a number by its reciprocal, the product is 1:
1*n = (3/2)*1
n = 3/2
Check. Substitute 3/2 for "n" in the original equation:
(2/3)*n = 1
(2/3)*(3/2) = 1
1 = 1
It checks.
If this is not what you meant in your problem, please respost clarifying your notation.