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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

It is known that people in the USA spend on average 15 hours a day using electronic devices with a standard deviation of 4.75 hours. This data follows a normal distribution. What is the probability someone spends more than 13 hours using electronic devices a day if it is known that they spend less than 20 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 accepts 70% 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 accepted into the PhD Program. (Hint: Binomial distribution with n=4, P=70%)   What is the probability that less than 2 students are accepted to the program? (round your answer to 4 decimal places)

In one study on the effect of Dyazide on blood pressure level, 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. In a second study, 25 subjects were randomly chosen to receive Dyazide and 25 were chosen to receive a placebo.Which of the following statement is correct?

Select the term that best fits this definition: As n increases the shape of the distribution will look more and more like a normal distribution

In One Sample Proportion test, it is important to convert the sample proportion to a z-score first. In this example, we selected a random sample of size 130 from a pool of university students and asked whether they use the university gym on a regular basis. Ninety replied yes. Assuming that the population proportion under the null hypothesis is 50%, what is the z-score (test statistics) for the sample proportion?

Select the term that best fits this definition: This equals the expected value of a sample mean for a sampling distribution