Statistics and Probability Answers

2. A teacher wants to investigate whether there is a difference between male and female students in the amount of time they spend studying for statistics. The table below shows the amount of time students spend studying statistics each week. The amounts of time spent studying are normally distributed.
Male Female
27 25
25 29
19 18
10 23
16 20
17 15
15 19
a. What statistical test should be used to analyze the data?

b. Is this a one- or two tailed test?

c. Identify H0 and Ha for this study.

d. Conduct the appropriate analysis. Should H0 be rejected?

What is the generic interpretation of a slope coefficient (i.e., b1 or b2) for a multiple regression?

Assume that the average annual salary for a worker in the United States is $35,000 and that the annual salaries for Americans are normally distributed with a standard deviation equal to 6,500. Find the following:

A-What percentage of Americans earn below $26,000.
B- What percentage of Americans earn below $26,000.

a coin is tossed 1 times .if head come accept outcome , if tail come toss the coin again and accept the outcome what is the probability of head occur?

What is the probability that the response time will be between five and ten minutes if the mean is 8.4 minutes and the standard deviation is 1.7 minutes?

In a store, an average of 10 customers enters per hour. What is the probability that at most 80 customers enter the store during a 10 hour day?

2. In roulette, the wheel contains 38 numbers. You pick a number, and the dealer spins the wheel. If the roulette ball lands on your number, you win.
a. What is the probability that you win on the 13th try?
b. Let’s say you bet 2 $ for every try, and make 10$ when you win. What is the probability that in 20 tries you don’t lose money?

During an epidemic of disease,
a doctor sees 110 people who have symptoms commonly associated with the
disease. Of these, 45 are women, of whom 20 actually have the disease. 15 of
the men also have the disease. Suppose a
person is selected at random from those with symptoms seen by the doctor. Define events:

W: the
selected person is a woman

D: the
selected person has the disease
(a)draw a Venn diagram for this problem
(b) Describe in words the events W, W È D, W Ç D, and W|D, and compute
probabilities associated with each of these events
(c) If three people are selected at random, what is the probability that
(i) all three of them have the disease
(ii)exactly one of them has the disease?
(d) Of people with the disease, 95% react positively to a diagnostic test, as also do 8% of people without the
disease. What is the probability of a person selected at random
(a) reacting positively
(b) having the disease given that he or she reacted positively?

FIND THE EXPECTED VALUE USING ADDITION RULES:
A 35 year old woman purchases a $100,000 term life insurance policy for an annual payment of $360. Based on a period life table for the U.S. government , the probability that she will survive the year is 0.999057. Find the expected value of the policy for the insurance company.
could you show me how this is done.

Use the given degree of confidence and sample data to construct a confidence interval for the population mean u, assume that the population has a normal distribution. N=12,x=21.3, s=6.3, 99%