A marketing survey of 2000 randomly-selected convenience store customers found that 1415 of them bought a glazed donut yesterday. 1605 said they bought a frosted crème-filled donut yesterday. 180 customers said they bought neither yesterday.
a. What is the probability that a single randomly-selected customer bought only a frosted crème-filled donut yesterday?
Enter answer rounded to the nearest thousandth (3 places after decimal).
b. For the Venn diagram above, let G = {customers who bought a glazed donut yesterday} and C = {customers who bought a frosted crème-filled donut yesterday}. Determine the number of attendees belonging to each of the diagram's regions I, II, III, IV in this order.
30,40,50,60 12,88,123,649
c. If the probability distribution for the random variable X is given in the table, what is the expected value of X?
Enter answer - with its sign - rounded to nearest hundredth (2 places after decimal)
xi -30 10 20 60
pi 0.40 0.30 0.20 0.10
E(x) =