Answer:
The customer can conclude that the company's claim is correct
Step-by-step explanation:
The percentage of lids that has a free yogurt coupon = 20%
The number of cups a loyal customer purchases = 85 yogurt cups
The number of cups that contained a coupon = 12 (14.1%)
The confidence interval performed = 99% confidence interval for the proportion of yogurt cups containing coupon codes
The interval obtained = (0.044, 0.238)
Therefore, the range of proportion within which the true proportion exists is 0.044 < < 0.238
The range of percentage within which the true percentage exist is therefore;
0.044 × 100 = 4.4% < × 100 < 0.238 × 100 = 23.8%
Given that the possible true percentage of lids that has a coupon is between 4.4% and 23.8% at 99% confidence level, the customer can conclude that only 12 of his yogurt cup contained coupon by chance and that the company's claim is correct.