At a local coffee shop, the manager has determined that 56% of drink orders are for specialty espresso drinks and 44% are for plain coffee. The manager also noted that 40% of customers order food. For customers who purchase the specialty espresso drinks, 35% also purchase a food item, and for customers who purchase plain coffee, 30% also purchase a food item. What is the probability that a randomly chosen customer will purchase a specialty espresso drink and a food item?

0.196

Step-by-step explanation:

Let :

Expresso drink = A

Plain coffee = B

Food = F

P(A) = 0.56

P(B) = 0.44

P(F) = 0.40

P(F|A) = 0.35

P(F|B) = 0.30

Probability that a customer purchases a specialty expresso coffee and a food item :

P(F|A) =. P(F n A) / P(A)

P(F n A) = P(F|A) * P(A)

P(F n A) = 0.35 * 0.56

P(F n A) = 0.196

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.