The given expression is 3 - 2/3. To subtract a fraction from a whole number, we need to convert the whole number into a fraction with the same denominator as the fraction. In this case, the denominator is 3. So, we convert 3 into a fraction by multiplying it by 3/3, which gives us 9/3. Now, we can subtract the fractions: 9/3 - 2/3 = 7/3. To express this as a mixed number, we divide the numerator (7) by the denominator (3), which gives us 2 with a remainder of 1. Hence, the answer is 2 1/3.