Question 1 of 1
In a consumer survey performed by a newspaper, 20 different groceries (products) were purchased in a grocery store. Discrepancies between the price appearing on the sales slip and the shelf price were found in 6 of these purchased products.
Let $ X $ denote the number of discrepancies when purchasing 3 random (different) products within the group of the 20 products in the store. What is the mean and variance of $ X $?