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Using the information below calculate the predicted value for Y for the given value of X. Y (Dependent Variable) = Cost of a car in thousands of dollars (i.e. Y = 1 means one-thousand dollars) X (Independent Variable) = Miles per Gallon in city traffic   yhat = 28.1 + 0.62*X   On average how many thousands of dollars would a car cost if it gets 30 Miles per Gallon in city traffic (round your answer to 4 decimal places)?

It is known that people in the USA spend on average 17 hours a day using electronic devices with a standard deviation of 7 hours. This data follows a normal distribution. What is the probability someone spends less than 20 hours using electronic devices a day if it is known that they spend more than 13 hours using electronic devices a day? (round your answer to 4 decimals) (Hint: Normal distribution and conditional probability)

In one study on the effect of Dyazide on blood pressure level, 25 subjects were randomly chosen to receive Dyazide and 25 were chosen to receive a placebo. These subjects were later examined to check for differences in their blood pressure levels. In a second study, 200 subjects who reported taking Dyazide for a long period of time had their blood pressure levels compared with those of 200 people who had never taken Dyazide. Which of the following statements is correct?

What is the clinical name of a probability that is used to determine the likelihood of someone having a disease when it is known they have a positive test.

What is the clinical name of a probability that is used to determine the likelihood of someone having a negative test when it is known they do have the disease.

It is known that people in the USA spend on average 18 hours a day using electronic devices with a standard deviation of 5.8 hours. This data follows a normal distribution. What is the probability someone spends less than 20 hours using electronic devices a day if it is known that they spend more than 13 hours using electronic devices a day? (round your answer to 4 decimals) (Hint: Normal distribution and conditional probability)

4 students apply to a PhD program.  The program rejects 45% of all applicants.  Students are accepted and rejected independently of each other.  Let the random variable X represent the number of the 4 students who get rejected into the PhD Program. (Hint: Binomial distribution with n=4, P=45%)   What is the standard deviation of the random variable?  (round your answer to 4 decimal places)

3 students apply to a PhD program.  The program rejects 65% of all applicants.  Students are accepted and rejected independently of each other.  Let the random variable X represent the number of the 3 students who get rejected into the PhD Program.    What is the probability that 1 student is rejected to the program if it is known that at fewer than 2 students will be rejected? (round your answer to 4 decimal places) (Hint: Binomial distribution with P=65% and n=3, and conditional probability)

The probability that a person tested positive on a screening test given that he/she has a disease is called the

A researcher would like to study BMI levels in adults 20-40 years of age. She selected 9 patients and found their BMI values to be: 28, 29, 20, 22, 25, 27, 26, 30, 37The mean BMI level of this group of patients is