A null hypothesis is that the probability is 0.7 that a new drug ...

[TVarnum]

A null hypothesis is that the probability is 0.7 that a new drug will provide relief in a randomly selected patient. The alternative is that the probability of relief is greater than 0.7 . Suppose the treatment is used on 500 patients and there are 380 successes. How would a p-value be calculated in this situation?
 a. Find the chance of 380 or more successes, calculated assuming the true success rate is greater than 0.7.
  b. Find the chance of 380 or more successes, calculated assuming the true success rate is 0.7.
  c. Find the chance of fewer than 380 successes, calculated assuming the true success rate is greater than 0.7.
  d. Find the chance of fewer than 380 successes, calculated assuming true success rate is 0.7.

Question 2

Grade school students, especially the ones in higher grades, tend to spend a lot of time on the computer already. The average amount of time 4th grade boys spend on the computer is 5 hours per week, with a standard deviation of 1 hour. For 5th grade boys the average increases to 7 hours per week with a standard deviation of 1.5 hours. Random sample of 20 4th grade students and 25 5th grade students are to be selected. What is the probability that the difference between the sample means is greater than 1 hour?

[jennafosdick]

Answer to Question 1

B

Answer to Question 2

0.9962

this gasoline tank claims that the actual capacity of a randomly selected tank has a distribution that is approximately normal with a mean of 15.0 gallons. A random sample of 25 tanks results in an average of 14.8 gallons with a standard deviation of 0.42 gallons.