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Question 259167: Use Chebyshev’s theorem to find what percent of the values will
fall between 10 and 26 for a data set with mean of 18 and standard
deviation of 2.

Use the Empirical Rule to find what two values 99.7% of the data
will fall between for a data set with mean 0 and standard deviation
of 12.
Click here to see answer by stanbon(57290)

Question 259255: A company buys calculators from a supplier.
The probability of a defective calculator is 10%. If three calculators are selected at random, what is the probability that none of the calculators will be defective? Show your work.

Click here to see answer by Fombitz(13828)

Question 259280: Suppose a fair coin is tossed twice. Find the probability for each of the following: exactly one head, at least one head, at most one head.
Please help. Thank you!
Click here to see answer by drk(1908)

Question 259299: ================== TEXT FOLLOWS
Staring with the data value 80 and 100. add three data values to the sample so that the mean is 94, the median is 94, and the mode is 94.
A class of 15 teachers had the following weights in pounds
48 39 54 46 50 54 36 44 54 35 36 54 39 42 43
find the mean, variance, and standard deviation
Click here to see answer by richwmiller(9135)

Question 259308: Suppose there are two green packages and five white packages in a sack. If two packages will be selected without replacement, what is the probability that the first package is white and the second package is green?
Click here to see answer by Fombitz(13828)

Question 259348: please I need your help!!!!!!!!!!!!!!
Starting with the data values 80 and 100, add three data values to the sample so that the mean is 94, the median is 94, and the mode is 94.

please help thank you
Click here to see answer by stanbon(57290)

Question 259382: The probability that San Francisco plays in the next Super Bowl is nine times the probability that they do not play in the next Super Bowl. The probability that San Francisco plays in the next Super Bowl plus the probability that they do not play is 1. What is the probability that San Francisco plays in the next Super Bowl?
Click here to see answer by Fombitz(13828)

Question 259392: a craftsperson is able to etch 25 windows per day if they are able to use the laser etching device, and 8 windows per day if they must etch by hand. if they can use the laser etching device 70% of the time, find the expected number of windows they etch per day
Click here to see answer by stanbon(57290)

Question 259454: A manufacturer finds the life expectancy of a dishwasher to be 11 years. The standard deviation for the lifespan is 1 year. What percent of the washers will last from 9 to 13 years?
Click here to see answer by stanbon(57290)

Question 259460: Four students bring lunches. All of the lunches get mixed up. What is the probability that exactly one student will get their own lunch?
Click here to see answer by stanbon(57290)

Question 259472: Containing the original 18 cookies find the probability of selecting two chocolate chip cookies without replacement
Click here to see answer by stanbon(57290)

Question 259643: There are 36 buttons in a jar. There are 3 times as many buttons as white buttons. So how many buttons are there? and How many red buttons are there? Please help me solve this problem.
Click here to see answer by richwmiller(9135)

Question 259647: There are 30 bows in a bag. There are 5 times as many small bows as large bows. So how many large bows are there? and how many small bows are there?
Click here to see answer by richwmiller(9135)

Question 259650: there are 36 buttons in a jar. There are 3 times as many red buttons as white buttons. So how many white buttons are there? and how many red buttons are there?
Click here to see answer by richwmiller(9135)

Question 259702: I need your help on this question of probability.... evaluate P (4, 4)
Click here to see answer by Fombitz(13828)

Question 259703: i need your help with this question.... evalutate C(7, 4) and this question also... evaluate 5!
Click here to see answer by stanbon(57290)

Question 259703: i need your help with this question.... evalutate C(7, 4) and this question also... evaluate 5!
Click here to see answer by Theo(3458)

Question 259687: You roll a conventional fair die repeatedly. If it shows I, you must stop, but you may choose to stop at any prior time. Your score is the number shown by the die on the final roll. What stopping strategy yields the greatest expected score? What strategy would you use if your score were the square
of the final roll?
Click here to see answer by edjones(7569)

Question 259607: imagen a table;
Fruit: Orange Apple Banana Strawberry other
Number of
students: 3 8 11 6 4

1) Suppose a student in the classroom is picked at random. Explain how to find the probability that the student's favorite fruit is strawberry.Express the probability in multiple ways.

2) Suppose a student in the classroom is picked at random. Explain how to find the probability that the student's favorite fruit is not an apple or a banana. Express the probability in multile ways.
-please explain throughly

Click here to see answer by edjones(7569)

Question 259799: I need your assistant please help thank you in advance
An quiz test has a mean of 45 and standard deviation of 15. Find the corresponding z scores for:
- a quiz score of 29
- a quiz score of 25
Please !!!!!!!!!!!!!!!!!!!!!!!!!!!! I'm really not sure
Click here to see answer by richwmiller(9135)

Question 259798: Can someone please put me on the right track i ask this question four time and no answer was given.

You are given the following frequency distribution for the number of errors that students made in a test
Errors Frequency
0-2 14
3-5 1
6-8 9
9-11 19
12-14 17
Find the mean, variance, and the standard deviation
please help ASAP!!!!!!!!!!!!!!!!!
Click here to see answer by richwmiller(9135)

Question 259840: Eight runners are competing in the 100-meter dash. In how many different ways can the runners finish? (Suppose there are no ties.) Please solve this question for me.
Click here to see answer by drk(1908)

Question 259872: In a batch of 10 light bulbs, two are known to be defective. If four bulbs are drawn at random, what is the probability of drawing 4 good bulbs?
Click here to see answer by scott8148(6628)

Question 259858: Sat verbal scores are normally distributed whith mean of 450 and a standard deviation of 50.
A. What percentage of students score less than 350?
B. What percentage of students score more than 400?
C. What percentage of students score less than 550?
D. What percentage of students score between 350 and 550?
E. An Ivy League university only admits students who are in the top 2.5% of scores on this test. What minimum score should a student get on this test to get admitted into this university?
Click here to see answer by stanbon(57290)

Question 259857: Light bulbs are measured in lumens (light output), watts (energy used), and hours (life). A soft white light bulb has a mean life of 700 hours and a standard deviation of 35 hours. Julia claims that the soft light bulbs she uses give a mean life of 800 hours. Use the z-score approach to test wether her claim is true or not.
Click here to see answer by stanbon(57290)

Question 259974: a manufacturer claims that the amount of peanuts contained in a jar follows normal distribution with the mean 7 ounces.A quality control inspector,however disagrees and believes it is some value below this figure.In order to test this belief the inspector takes random variable 25 jars and finds that the sample mean is 6.5 and sample standard deviation 0.9 ounces.
- what is probability of sample mean smaller than 6.5
-what are the null and alternative hypothesis inspector should test?
Click here to see answer by stanbon(57290)

Question 259970: A die contains the numbers one through six. If the die is rolled twice, what is the probability of it landing on five in two consecutive tosses?
(A) 2/6 (B) 5/6 (C) 1/36 (D) 10/36 (E) 25/36
Click here to see answer by stanbon(57290)

Question 259927: Hello Again,
I had already sent this question and got part of the answer but I had forgot to send the second part, and I think that I figured out the second part but not for sure I may be wrong.
Question:
2.Use the method specified to perform the hypothesis test for the population
mean . A local brewery distributes beer in bottles labeled 32 ounces. A government agency thinks that the brewery is cheating its customers. The agency select 50 of these bottles, measures their contents, and obtains a sample mean of 31.6 ounces with a population standard deviation of 0.70 ounce. At - this symbol means the level of significance alpha = 0.01, test the agency’s claim that the brewery is cheating its customers
b. Use the P-value method.
1. H0 : u=32
Ha :
2.  = u is greater than 32
3. Test statistics: 31.6-32/0.7/square root 50=4.0406
4. P-value or critical z0 or t0. df (-100 -4.0406.49) =0.0009379
5. Rejection Region:

6. Decision:
7. Interpretation:
I am going based on from what I had gotten help on the first part of the question, and also I based it on the formula used in the book.

Click here to see answer by stanbon(57290)

Question 259831: According to the National Association of Home Builders, the median selling price of new homes in the United States in 2002 was $187,100. Which of the following is the most plausible value for the standard deviation: $15,000, $1000, $60,000, or $1,000,000. why?
Click here to see answer by stanbon(57290)

Question 259817: Can you please help with this statistics problem?
During the period 1990-1998 there were 46 Atlantic hurricanes, of which 19 struck the United States. During the period 1999-2006 there were 70 hurricanes, of which 45 struck the United States.
a) What is the appropriate null and alternate hypothesis to determine if the
proportion of hurricanes striking the United States increased?
b) Using α = 0.01, what is the critical value for the hypothesis test?
c) What is the test statistic for the hypothesis test?
d) Draw a conclusion for the hypothesis test. Make sure you state your conclusion in the context of the problem.
e) What is the p-value for the hypothesis test?
Thank you!
Click here to see answer by stanbon(57290)

Question 259984: Police use photographs of various facial features to help witnesses identify suspects. One basic identification kit contains 195 hairlines, 99 eyes and eyebrows, 89 noses, 105 mouths, and 74 chins and cheeks. The developer of the identification kit claims that is can produce billions of different faces. Is this claim correct?
Click here to see answer by stanbon(57290)

Question 260057: Can someone please help me understand this?
If 12 drivers were randomly selected, what is the probability of getting 0 who were involved in a car accident last year?
a. Set up a probability distribution to describe this situation.
b. Based on these probabilities how many defective computers would you expect to find in this batch? (This would be the mean of the distribution.)
c. How much would this value reasonably be expected to fluctuate? (This is the standard deviation.)

Click here to see answer by richwmiller(9135)

Question 260059: I do not understand this at all and need some help please.
The table below describes the smoking habits of a group of asthma sufferers.
Gender - Non Smoker - light Smoker - heavy Smoker - Total
Men 432 35 31 498
Women 438 39 43 520
Total 870 74 74 1018
a. If a person is randomly selected, find the probability that he or she is not a light smoker.
b. If a person is randomly selected, find the probability of getting a woman given that she is a nonsmoker.
c. Assuming we were to consider a random sample of 13,000 people, how many would you predict are men who are heavy smokers based on the results given here?

Click here to see answer by richwmiller(9135)

Question 260070: two groups of patients were given. eight in each group. the mean and standard deviation of both groups given.
carry out a formal test of hypothesis that the population means are the same. what assumptions are required for this test.
obtain a 95% confidence interval for the difference between population means
plz tell how to do this
Click here to see answer by stanbon(57290)

Question 260055: Five couples (ten people) are standing in line. If the order is completely random, what is the probability that each person will be standing next to his/her spouse?
Click here to see answer by edjones(7569)

Question 260024: The game of dots is played by rolling a fair die and
receiving $1 for each dot showing on the top face of the
die. What cost should be set for each roll if the game is
to be considered a fair game?
Click here to see answer by checkley77(12569)

Question 260011: There are three different kinds of socks in a bag: red, blue, and yellow. The probability of choosing a red sock is 1/5. If there are twice as many blue socks as red socks, what is the probability of choosing a yellow sock?
Click here to see answer by edjones(7569)

Question 260099: Can someone please help me understand this.
Based on past records, a car insurance company has determined that 9% of all drivers were involved in a car accident last year.
a. If 12 drivers were randomly selected, what is the probability of getting 0 who were involved in a car accident last year?
b. If 12 drivers were randomly selected, what is the probability of getting 3 or more who were involved in a car accident last year?

Click here to see answer by stanbon(57290)

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