Final answer:
The mean sample proportion is 0.67 and the standard sample proportion is 0.0235.
Step-by-step explanation:
To find the mean of a sample proportion, multiply the proportion (p) by the sample size (n). In this case, the proportion is 0.67 (67% as a decimal) and the sample size is 256. So the mean is 0.67 * 256 = 171.52.
To find the standard deviation of a sample proportion, use the formula: √((p * (1 - p)) / n). Plugging in the values, the standard deviation is √((0.67 * (1 - 0.67)) / 256) = 0.0235.
Therefore, the mean sample proportion is 0.67 and the standard sample proportion is 0.0235.