At a college hot dog eating contest, you noticed some interesting facts about the participants. 60% of the eaters were students and 40% were faculty. Furthermore, among the student eaters, 70% were men and the rest were women. On the other hand, among the faculty eaters, 60% were women and the rest were men.
A) What is the probability that a randomly selected participant was a woman?
B) What is the probability that a randomly selected participant was a man and a faculty member?
C) What is the probability that a randomly selected participant was a man or a student?
D) Given a randomly selected participant was a woman, what is the probability that she was a faculty member?
In: Statistics and Probability
4. A) The probability that a student from a certain university has a cell phone is 0.2. So, the probability that the tenth student randomly interviewed at this university is the fifth with Cell phones is:
B) On a certain day, the second stage of the environmental contingency plan was implemented in the Mexico City. If there are 50 companies in the area that corresponds to a supervisor, of which 15 did not follow contingency guidelines, then the probability that 3 companies out of the 10 that are verified will not follow the guidelines is:
C)If the planes arriving at an airport follow a Poisson process with an average rate of 8 planes per hour. The probability of exactly 10 aircraft arriving in the next 2 hours is as close to:
In: Statistics and Probability
The mean age for a person getting married for the first time is 27.3 years. Assume the ages for first marriages are normal with a standard deviation of 4.9 years. (Give probability answers to four decimal places.)
a) What is the probability that a person being married for the first time is between 23.6 and 31.7 years old?
b) What is the probability that a person being married for the first time is over 33.1 years old?
c) What is the probability that a person being married for the first time is between 25.4 and 33.8 years old?
d) 75% of people getting married for the first time do so before what age?
In: Statistics and Probability
Web crawlers need to estimate the frequency of changes to Web sites to maintain a current index for Web searches. Assume that the changes to a Web site follow a Poisson process with a mean of 3.5 days.
a) (6 pts) What is the probability that the next change occurs in less than 2.0 days?
b) (6 pts) What is the probability that the time until the next change is greater 7.0 days?
c) (6 pts) What is the time of the next change that is exceeded with probability 90%?
d) (7 pts) What is the probability that the next change occurs in less than 10.0 days, given that it has not yet occurred after 3.0 days?
In: Statistics and Probability
An engineer is going to redesign an ejection seat for an airplane. The seat was designed for pilots weighing between 150 lb and 201 lb. The new population of pilots has normally distributed weights with a mean of 159 lb and a standard deviation of 34.3 lb lb. a. If a pilot is randomly selected, find the probability that his weight is between 150 lb and 201 lb. The probability is approximately 0.4931. (Round to four decimal places as needed.) b. If 30 different pilots are randomly selected, find the probability that their mean weight is between 150 lb and 201 lb. The probability is approximately ___. (Round to four decimal places as needed.)
In: Statistics and Probability
A box in a certain supply room contains five 40-W lightbulbs, six 60-W bulbs, and four 75-W bulbs. Suppose that three bulbs are randomly selected. (Round your answers to four decimal places.)
(a) What is the probability that exactly two of the selected
bulbs are rated 75-W?
(b) What is the probability that all three of the selected bulbs
have the same rating?
(c) What is the probability that one bulb of each type is
selected?
(d) Suppose now that bulbs are to be selected one by one until a
75-W bulb is found. What is the probability that it is necessary to
examine at least six bulbs?
In: Statistics and Probability
You and a friend are rolling a set of 8 dice. The game works such that if a die shows the values 1, 2, 3, or 4 you will get a point for that die. Each die that shows 5 or 6 your friend will get a point for. Construct a probability model for a single roll of the dice then answer the following.
Step 2 of 5: What is the probability that your friend will score 2 points?
Step 3 of 5:
What is the probability you score 4 or more points in this round?
Step 4 of 5:
If we play a second round of this game, what is the probability that you will have exactly 6 points at the end of the second round?
In: Statistics and Probability
1.In a statistics course, the average student result is 69.6% with the standard deviation of 9.4%. If Jake has completed the course with the score of 92.5%, what was Jake's z-Score
2.Find the probability to obtain 4 as the sum of dots, when two dice are tossed (one die is red and the other is blue). Round the answer to three decimal places. For example, for probability 0.05673, type 0.057.
3.Find the probability to obtain the sequence HTHT, when 4 coins are tossed one after another. Here H is "Head" and T is "Tail". Round your answer to 4 decimal places. For example, for probability 0.34123, type 0.3412
In: Statistics and Probability
In: Statistics and Probability
The mean age for a person getting married for the first time is 25.4 years. Assume the ages for first marriages are normal with a standard deviation of 4.9 years. (Give probability answers to four decimal places.)
a) What is the probability that a person being married for the first time is between 21.7 and 33.4 years old?
b) What is the probability that a person being married for the first time is over 29.1 years old?
c) What is the probability that a person being married for the first time is between 18.6 and 32.8 years old?
d) 85% of people getting married for the first time do so before what age?
In: Statistics and Probability