The soft-drink cups at a certain fast-food restaurant have tickets attached to them. Customers peel off the tickets to see whether they win a prize. The proportion of tickets that are winners is p = 0.30. A total of n = 85 people purchase soft drinks between noon and 1:00 PM on a certain day. Let be the proportion that win a prize. Find the mean and standard deviation of sample proportion (P.). Formula: 1. The mean of the sampling distribution of population proportion: is denoted by and equals the p = P 2. The standard deviation of the sampling distribution of p(1-p) is denoted by , is: