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Question 329553: Mary Martinez loves to weigh things with her new electronic scale that is accurate to the nearest gram. Mary has always wondered whether or not the cereal inside the boxes of her favorite brand actually weighs 300 grams as shown on the carton, so she decides to weigh the cereal inside the next 21 boxes that she buys. Results are as follows:
297 303 289 314 302 301 300
302 288 294 296 297 300 299
391 287 286 288 295 298 302
The sample mean = 301.38 grams and the sample standard deviation = 21.60 grams.

State the appropriate null and alternative hypotheses.

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Question 329602: an election poll reported that a candidate had an approval rating of 51% with a margin of error E of 3%. Construct a confidence interval for a proportion of adults who approve of the candidate.
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Question 329640: Is there any website which helps for the problems in probability theory and stochastic processes(PTSP). if any body gives i will be very thankful to them
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Question 329675: A highly selective boarding school will only admit students who place at least 1.5 z-scores above the mean on a standardized test that has a mean of 110 and a standard deviation of 12. What is the minimum score that an applicant must make on the test to be accepted?
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Question 329739: A contractor is considering a sale that promises a profit of $20,000 with a probability of .7 or a loss (due to bad weather, strikes, and such) of $3000 with a probability of .3. What is the expected profit?
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Question 329738: A contractor is considering a sale that promises a profit of $20,000 with a probability of .7 or a loss (due to bad weather, strikes, and such) of $3000 with a probability of .3. What is the expected profit?
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Question 329701: There is a class of 24 students, 10 girls and 14 boys. If the teacher randomly selects a student to be the hall monitor, what is the probability the hall monitor will be a girl? Write as fraction.
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Question 329682: One personality test available on the World Wide Web has a subsection designed to assess the "honesty" of the test-taker. After taking the test and seeing your score for this subsection, you're interested in the mean score, µ, among the general population on this subsection. The website reports that µ is 140, but you believe that µ is greater than 140. You decide to do a statistical test. You choose a random sample of people and have them take the personality test. You find that their mean score on the subsection is 145 and that the standard deviation of their scores is 25.
What are the null hypothesis ( Ho ) and the alternate hypothesis( H1) that should be used in the test.?
In the context of this test, what is the type 1 error?
A type 1 error is __________________the hypothesis that is µ is ________when, in fact, µ is___________
Suppose the consultant decides to reject the null hypothesis. What type of error might she be making?

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Question 329679: Executives of a supermarket chain are interested in the amount of time that customers spend in the stores during shopping trips. The mean shopping time, µ spent by customers at the supermarkets has been reported to be 35 minutes, but executives hire a statistical consultant and ask her to determine whether it can be concluded that µ is greater than 35 minutes .
To perform her statistical test, the consultant collects a random sample of shopping times at the supermarkets. She computes the mean of these times to be 40 minutes and the standard deviation of the times to be 12 minutes.
What are the null hypothesis ( Ho ) and the alternate hypothesis( H1) that should be used in the test.?
In the context of this test, what is the type II error?
A type II error is __________________the hypothesis that is µ is ________when, in fact, µ is___________
Suppose the consultant decides to reject the null hypothesis. What type of error might she be making?

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Question 329765: Find the mean for the following. Round to the nearest tenth. Value Frequency 9 3 12 5 15 1 18 1 must show work.

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Question 329773: A coin-operated drink machine was designed to discharge a mean of 6 ounces of coffee per cup. In a test of the machine, the discharge amounts in 20 randomly chosen cups of coffee from the machine were recorded. The sample mean and sample standard deviation were 6.13 ounces and 0.23 ounces, respectively. If we assume that the discharge amounts are normally distributed, is there enough evidence, at the 0.05 level of significance, to conclude that the true mean discharge, µ, differs from 6 ounces?
Perform a one-tailed test
Null Hypothesis: Ho
Alternative Hypothesis: H1
Type of Test Statistic:
The Value of the Test Statistic:

The two critical values at the 0.05 level of significance.
At the 0.05 level of significance, can we conclude that the true mean discharge differs from 6 ounces?

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Question 329827: Of 100 students, 37 play an instrument, 45 play sports, and 11 do both. What is the probability that a student neither plays an instrument nor plays sports?
(A) 0.145 (B) 0.18 (C) 0.29 (D) 0.40 (E) 0.82

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Question 329815: The probability that a football player will play Eden garden is 0.6 and on Ambedkar Stadium is 0.4. The probability that he will get knee injury when playing in Eden is 0.07 and that in Ambedkar stadium is 0.04.What is the probability that he would get a knee injury if he played in Eden.
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Question 329981: A plane with a tail wind makes its 785-mile flight in 2.5 hours. The return flight against the wind takes a half hour longer. What is the wind speed (rounded to the nearest mile per hour)?
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Question 329987: A common error is neglecting to get ranked data for some statistical processes. Why do we have to have ranked data? Give an example of where you would need ranked data.
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Question 330018: How many different ways can 12 questions on a true false test be answered if a student answers every question.
I have... 12 questions each with 2 possible answers so... 24 different ways...is that right?
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Question 330050: Here is my question.
At a quality control checkpoint on a manufacturing assembly line, 8% of the items failed check A, 10% failed check B, and 2% failed both checks A and B.
a. If a product failed check A, what is the probability that it also failed check B?
b. If a product failed check B, what is the probability that it also failed check A?

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Question 330070: The standardized mathematics scores of a certain school district are normally distributed with the mean of 500 and standard deviation 100. Find the probability that a score is less than 300?
I have no idea where to start. a clue would be great. Have another homework question just like it.
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Question 330098: Your friend randomly selects 2 movies from your collection to borrow. Your collection includes 9 comedies, 5 dramas, 3 mysteries, 1 musical, and 2 horror movies. What is the probability that both movies are comedies?
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Question 330194: Someone Please help with these problems. The answers I came with I was told was incorrect if possible can you provide the formula you used as I want to take notes. This is the hardest class I have ever taken :(
1.Consider the probability experiment of drawing one card from a deck of cards.
a)Determine the sample space of the probability experiment.
ANS:
3.Compute the probability that a randomly selected person does not have a birthday in January. Show the formula you have used.

4.In how many ways you can randomly select 5 students from a 12-student class?
5.In how many ways can 3 students (randomly select from a 12-student class) be lined up?
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Question 330236: 3.Compute the probability that a randomly selected person does not have a birthday in January. Show the formula you have used.
In how many ways can 3 students (randomly select from a 12-student class) be lined up. NOTE I can out with 220
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Question 330242: How many ways can 3 cards be drawn from an ordinary 52-card deck?
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Question 330240: How many ways are there to cover 2 chairs of a row of 8 chairs?
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Question 330243: How many ways can 3 cards containing no face card (J,Q,K) be drawn from an ordinary 52-card deck?
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Question 330243: How many ways can 3 cards containing no face card (J,Q,K) be drawn from an ordinary 52-card deck?
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Question 330268: 18 Sixty-four students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Research question: At α = .01, is the degree of certainty independent of credits earned?
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Question 330304: Hello Can someone advise if this right. I hope I used the correct formula
In how many ways you can randomly select 5 students from a 12-student class?
ANS: 12C5 = (12*11*10*9*8)/(1*2*3*4*5) = 792

Also Can some please advise on the bwlow item I ansewered question B but I am not the greatest with Sample Space.
Consider the probability experiment of drawing one card from a deck of cards.
a) Determine the sample space of the probability experiment.
ANS:
b) Determine the probability of randomly selecting a face (Q, J or K) card.
ANS: 12/52=.23

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Question 326907: event A occurs with probabity 0.1. Event B occurs with probability 0.6. if A and B are independant, then :
a- p(a and b)= 0.70
b- p(a or b)= 0.64
c- p(a and b)= 0.64
d- p(a or b)= 0.70
thanks

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Question 330337: does lovastatin reduce the risk of heart attack. In a texas study,
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Question 330336: does lovastatin reduce the risk oh heart attack
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Question 330342: 34. If the Independent Party has lost 10 of the last 15 elections, find the odds against an Independent victory in the next election.
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Question 330345: 28. Identify the binomial expansion of (x + 4y)4.
1. x4 + 256y4
2. x4 + 8x2y2 + 16y4
3. x4 + 12x3y + 96xy3 + 256y4
4. x4 + 16x3y + 96x2y2 + 256xy3 + 256y4

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Question 330331: The Web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the sa
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Question 330411: P(x> or equal to 2) mu=3 and standard deviation =0.25
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Question 330396: When we carry out a chi-square test of independence, as the difference between the respective observed and expected frequencies decrease, the probability of concluding that the row variable is independent of the column variable:
Decreases
Increases
May decrease or increase depending on the number of rows and columns
Will be unaffected

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Question 330398: I am completely lost trying to figure out these tables! I would love some help trying to figure it out!! Thanks!

The frequency distribution shown lists the number of hours per day a randomly selected sample of teenagers spent watching television.
Hours per day # of teens = f Midpoint = x Fx Fx²
0 ≤ x < 1 18
1 ≤ x < 2 31
2 ≤ x < 3 24
3 ≤ x < 4 38
4 ≤ x < 5 27
5 ≤ x < 6 12
6 ≤ x < 7 15
a. Complete the table.
b. Construct a histogram representing the data.
c. Calculate the mean, median, and mode number of hours the teens watch television.
d. Calculate the standard deviation.
e. What percent of the data lies within one standard deviation of the mean?

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Question 330394: Given the following information about a hypothesis test of the difference between two variances based on independent random samples, what is the calculated value of the test statistic? Assume that the samples are obtained from normally distributed populations.

F = 2.0
F = 3.0
F = 1.667
F = 1.778
F = 2.778

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Question 320334: A box contains 24 widgets, 4 of which are defective. If 4 are sold at random, find the probability that a) all are defective b) none are defective.
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Question 283069: what is the probability of 3 cars all having the exact same malfunction at nearly the same time?
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Question 330559: How many different license plates can be made using 3 letters followed by 3 digits selected from the digits 0 through 9, if letters and digits may be repeated?
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Question 329834: I Need Help please :-(!!!!
What is the probability that at least 3 red cards will be drawn from a 52 card deck?
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Question 329835: I have no idea where to start with this.... Thanks for your help!
11 out of 40 students are selected for a team each year. 15/40 participated once in the last two years. What is the probability of selecting 3 but no more than 5 students from the 15 that previously participated.
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