# Question

Customers at a fast-food restaurant buy both sandwiches and drinks. The following joint distribution summarizes the numbers of sandwiches (X) and drinks (Y) purchased by customers.

(a) Find the expected value and variance of the number of sandwiches.

(b) Find the expected value and variance of the number of drinks.

(c) Find the correlation between X and Y.

(d) Interpret the size of the correlation for the manager of the restaurant.

(e) If the profit earned from selling a sandwich is $1.50 and from a drink is +1.00, what is the expected value and standard deviation of the profit made from each customer?

(f) Find the expected value of the ratio of drinks to sandwiches. Is it the same as μY / μX?

(a) Find the expected value and variance of the number of sandwiches.

(b) Find the expected value and variance of the number of drinks.

(c) Find the correlation between X and Y.

(d) Interpret the size of the correlation for the manager of the restaurant.

(e) If the profit earned from selling a sandwich is $1.50 and from a drink is +1.00, what is the expected value and standard deviation of the profit made from each customer?

(f) Find the expected value of the ratio of drinks to sandwiches. Is it the same as μY / μX?

## Answer to relevant Questions

During the 2010-2011 NBA season, LeBron James of the Miami Heat attempted 279 three-point baskets and made 92. He also attempted 1,485 two-point baskets, making 758 of these. Use these counts to determine probabilities for ...A construction firm places bids on various portions of the work in building a new office tower. The key bids it submits are for electrical work and for plumbing. The bid for the electrical work estimates 64 weeks of labor ...Is the binomial model suited to these applications? (a) The next five cars that enter a gasoline filling station get a fill-up. (b) A poll of the 15 members of the board of directors of a company indicates that 6 are in ...A manufacturer of LCD panels used in computer displays has decided to ship only panels with at most one defective pixel. Defective pixels are the result of randomly located flaws in the glass used to make the panel. To be ...A marketing research firm interviewed visitors at a car show. The show featured new cars with various types of environmentally oriented enhancements, such as hybrid engines, alternative types of fuels (such as bio fuels), ...Post your question

0