If 47 out of 75 customers are somewhat or very satisfied with your customer service, then what is Hint: Make a Tree Diagram or a two-way contingency table p, the sample proportion? a) Find the probability that a person has the virus given that they have tested positive, Le. find P(A| B). Answer as a probability (proportion--not percent). Round your answer to at lea If you make a 95% confidence interval, what is the parameter you are estimating? three decimals. P(AIB) b) Find the probability that a person does not have the virus given that they test negative, i.e. find P(!A | !B). Round your proportion to at least three decimals. P(!A | !B) = Correct 3. Giving a test to a group of students, the grades and gender are summarized below If you want to compute a 95% confidence interval for the parameter, what are the assumptions that must be true? A B C Total "the original variable is normally distributed Male 15 20 8 43 Female 3 10 11 24 n*p is large AND n*(1-p) is large (at least 5) Total 18 30 19 67 n*p is large n2 30 If one student is chosen at random, Find the probability that the student was female OR got an "C". Correct What is n*p? 4. 40% of Americans start the day with a cereal breakfast. Based on this information, consider the sampling distribution of the proportions of Americans who start the day with a cereal breakfast in random samples of size 60. What is n* (1-p)? First, find n'p: First, find n'(1-p): 2. A certain virus infects one in every 300 people. A test used to detect the virus in a person is positive 90% of the time if the person has the virus and 8% of the time if the person does not have the virus. (This 8% result is called a false positive. ) Let A be the event "the person is infected" and B be the event "the person tests positive"