Concept explainers
In considering medical insurance for a certain operation, let X equal the amount (in dollars) paid for the doctor and let Y equal the amount paid to the hosp ital. In the past, the variances have been
Due to increased expenses, it was decided to increase the doctor’s fee by $500 and increase the hospital charge Y by 8%. Calculate the variance of
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Probability And Statistical Inference (10th Edition)
- There is a p(x1) = 0.4 probability to observe x1 = 10 and p(x2) = 0.6 probability to observe x2 = 5. Find the mean and the variance of x. Show work.arrow_forwardCould you please teel me why should a firm, for profit, care not only about the expected profit, but also about the variance of the profit.thanksarrow_forward(a) In each Australian capital city, a large retail chain has several stores, including in Brisbane and Perth. An analysis of the variations in profits from each of these cities indicates that the variance of monthly profits in Brisbane is about 2570(k$)^2 and the variance of monthly profits in Perth is about 1789(k$)^2 . A comparison of the difference in profits between the two cities indicates that the variance of the monthly difference in profits between these cities is about 1253(k$)^2 . (i) Calculate the covariance between the two cities' monthly profits using this information. (ii) Find the correlation (ρ) between the monthly profits in these two cities. (b) Quality control staff wish to estimate what proportion p of the resistors made in their factory are scrapped due to defects. Based on a random sample of n = 750 resistors from the production line, they calculate the scrapped resistor proportion to be ˆp = 0.016. Use this information to determine an approximate range a. This…arrow_forward
- (a) In each Australian capital city, a large retail chain has several stores, including in Brisbane and Perth. An analysis of the variations in profits from each of these cities indicates that the variance of monthly profits in Brisbane is about 2570(k$)^2 and the variance of monthly profits in Perth is about 1789(k$)^2 . A comparison of the difference in profits between the two cities indicates that the variance of the monthly difference in profits between these cities is about 1253(k$)^2 . (i) Calculate the covariance between the two cities' monthly profits using this information. (ii) Find the correlation (ρ) between the monthly profits in these two cities. (b) Quality control staff wish to estimate what proportion p of the resistors made in their factory are scrapped due to defects. Based on a random sample of n = 750 resistors from the production line, they calculate the scrapped resistor proportion to be ˆp = 0.016. Use this information to determine an approximate range a. This…arrow_forwardIn testing the lethal concentration of a chemical found in polluted water, it is found that a certain concentration will kill 20% of the fish that are subjected to it for 24 hours. If 20 fish are placed in a tank containing this concentration of the chemical, a) find the number expected to survive out of 20 b) Find the variance of the number of survivors out of 20.arrow_forwardWhat is the variance of Y_k+1arrow_forward
- A snack food manufacturer estimates that the variance of the number of grams of carbohydrates in servings of its tortilla chips is 1.25. A dietician is asked to test this claim and finds that a random sample of 22 servings has a variance of 1.35. At ⍶ = 0.05 is there enough evidence to reject the manufacturer’s claim?arrow_forwardFind the variance of X + 3Y + Z + 6 in terms of the variances and covariances of X, Y, and Z.arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill