Final answer:
The probability distribution of X follows a binomial distribution. The mean of X is 65 and the standard deviation of X is approximately 7.527.
Step-by-step explanation:
The probability distribution of X, the number of households including at least one college graduate, follows a binomial distribution since there are only two outcomes for each household: including at least one college graduate or not. The mean of X can be calculated using the formula: mean = n * p, where n is the number of trials and p is the probability of success. The standard deviation of X can be calculated using the formula: standard deviation = sqrt(n * p * (1 - p)).
For this problem, n = 100 (since 100 households were sampled) and p = 0.65 (since 65% of households include at least one college graduate).
Using the formulas, we can calculate:
Mean = 100 * 0.65 = 65
Standard Deviation = sqrt(100 * 0.65 * (1 - 0.65)) = sqrt(100 * 0.65 * 0.35) ≈ 7.527