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Question 171714: I need someone to double check my work.
Two dice are rolled. Find the probability that the score on the dice is either 7 or 9?
Possibilities for 7 are (4,3)(5,2)(6,1) which = 3/36 = 1/12 = 0.083333 (8%)
Possibilities for 9 are (6,3)(4,5)which = 2/36 = 1/18 = 0.055555 = (6%)
Did I work these problems right?

Click here to see answer by stanbon(57984)

Question 172026: a school board plans to merge 2 schools into a school of 1000 students of which 42% will be african american. One of the schools has a 10% african american student body and the3 other has a 90% african american student body. What is the studen population in each of the two schools?
Click here to see answer by Earlsdon(6294)

Question 172110: A survey of undergraduate students in the School of Business at Northern University revealed the following regarding the gender and majors of the students:
Major
Gender Accounting Management Finance Total
Male 100 150 50 300
Female 100 50 50 200
Total 200 200 100 500

a) What is the probability of selecting a female student?
b) What is the probability of selecting finance or accounting major?
c) What is the probability of selecting a female or an accounting major? Which rule of addition did you apply?
d) Are gender and major independent? Why?
e) What is the probability of selecting an accounting major, given that the person selected is a male?
f) Suppose two students are selected randomly to attend a lunch with the president of the university. What is the probability that both of those students are accounting majors?

Click here to see answer by stanbon(57984)

Question 172151: A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were
3.087 3.131 3.241 3.241 3.270 3.353 3.400 3.411 3.437
(a) Construct a 90 percent confidence interval for the true mean weight. (b) What sample size would be necessary to estimate the true weight with an error of ± 0.03 grams with 90 percent confidence? (c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during manufacture. (Data are from a project by MBA student Henry Scussel.) Tootsie

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Question 172165: An industrial process that makes 3-foot sections of plastic pipe produces pipe with an average inside diameter of 1 inch and a SD of 0.05 inch. If you randomly select one piece of pipe what is the probability that its inside diameter will exceed 1.02 inch assuming the population is normal.
Click here to see answer by stanbon(57984)

Question 172298: Suppose that 7 cards are drawn from a well shuffled deck of 52 cards. What is the probability that they are call clubs?

Click here to see answer by Mathtut(3670)

Question 172292: In a chemistry class, there are as many men as there are woman. On a final exam, the mean score for the women was 93 while the mean score for the men was 81. What was the mean score for the entire class?
Click here to see answer by ilyblackberrykid13(1)

Question 172500: A TEST IS NORMALLY DISTRIBUTED WITH A MEAN OF 200 AND A STANDARD DEVIATION OF 10, FIND P40.
Click here to see answer by stanbon(57984)

Question 172511: A COMMITTE OF 5 MEMBERS IS FORMED FROM A FROUP OF 10 REPUBLICANS AND 8 DEMOCRATS.
A) FIND THE PROBABILITY OF SELECTING ALL DEMOCRATS
B) FIND THE PROBABILITY OF SELECTING 2 DEMOCRATS AND 3 REPUBLICANS
Click here to see answer by stanbon(57984)

Question 172516: MEN WEIGHT ON AVERAGE IS 165lbs WITH A S.D OF 35lbs...
A)WHAT IS THE PROBABILITY THAT CARL WEIGHS MORE THAN 190lbs
B)WHAT IS THE PROBABILITY THE MEAN WEIGHT OF A GROUP OF 40 MEN IS MORE THAN 190lbs
Click here to see answer by stanbon(57984)

Question 172515: PLEASE HELP ME!!!!!! I AM STUDYING FOR MY FINAL EXAM....
15 ARROWS ARE SENT TO HIT A TARGET. THE PROBABILITY THAT ANY OF THE ARROWS HITS THE TARGET IS 0.7. WHAT IS THE PROBABILITY THAT AT LEAST 7 ARROWS HIT THE TARGET?
Click here to see answer by stanbon(57984)

Question 172513: THE TIRE COMPANY CLAIMS THAT ITS TIRES LAST AN AVERAGE 50K WITH A S.D OF 15K. BASED ON THE SAMPLE SIZE 33, WITH A SAMPLE MEAN OF 52K AND A LEVEL OF SIGNIFICANCE OF ()=0.1; TEST THE CLAIM USING HYPOTHESES TESTING TECHNIQUES AND WRITE YOUR CONCLUSION IN NON-TECHNICAL TERMS.
Click here to see answer by stanbon(57984)

Question 172727: During her four years at college, Rose received the following amounts of money at the end of each year from her grandmother. She deposited her money in a saving account paying 6 percent rate of interest. How much money will Rose have on graduation day?
Year $
1 100
2 200
3 300
4 400

Click here to see answer by w1ldc4t(2)

Question 172512: A TEST IS NORMALLY DISTRIBUTED WITH A MEAN OF 72.5 AND A STANDARD DEVIATION OF 4, WHAT IS THE PROBABILITY OF GETTING MORE THAN73.5 IN THIS TEST?
Click here to see answer by stanbon(57984)

Question 173102: A. A fair coin is tossed THREE times. What is the probability that you get at least ONE tail?
B. What is the probability that you are dealt a poker hand contains all FACE cards ( i.e. KING, QUEEN, JACK)?

Click here to see answer by checkley77(12569)

Question 173101: A. In how many ways can 15 books be arranged on a shelf?
B. In how many ways can different committees of 8 people be formed from a pool of 10 people?

Click here to see answer by stanbon(57984)

Question 173091: The inside diameter of metal washers produced by a company are normally distributed with a mean of 0.5 inches and a standard deviation of 0.01 inches. Of all washers produced, 0.8% of the washers are rejected because they are to small for a bolt used to test them. What is the diameter of the bolt used for the test?
I have tried almost every formula and I cannot seem to get this one at all, please help! Thanks
Click here to see answer by stanbon(57984)

Question 173286: Dave invested $8,500 in a time deposite. What interest will he earn for 2 years if the interest rate is 4.75 percent?
Click here to see answer by stanbon(57984)

Question 173316: grace has 16 jellybeans in her pocket. she has 8 red ones, 4 green ones, and 4 blue ones. what is the minimum number of jellybeans she must take out of her pocket to ensure that she has one of each color.
Click here to see answer by checkley77(12569)

Question 173377: how would you find the inverse of {(2,0), (4,3), (5,1)}
Click here to see answer by Mathtut(3670)

Question 173374: is f(x)*g(x) the same as f(g(x)) ?
Click here to see answer by Mathtut(3670)

Question 173376: can you help me with this problem:
f(x)=-^3square rootx+2 not under square root -1
sorry if it's confusing.
Click here to see answer by Mathtut(3670)

Question 173396: From the ski lodge example, suppose that the probability of breaking your leg is 0.20. (Therefore the probability of not breaking your leg is (1 – 0.20) = 0.80.) What is the probability that exactly 2 out of 5 people will break their leg? n = 5, x = 2, p = .2, q = .8. What is the probability that less than 2 out of 5 people will break their leg?
Click here to see answer by stanbon(57984)

Question 173545: find the number of possible outcomes by drawing a tree diagram: choosing four cards from a standard 52-deck???
Click here to see answer by checkley77(12569)

Question 173645: 1. Find the probability of 7 tomatos getting accepting in 6 stores when the mean is 5.5
2.Random sample of 120 customers’s spent an average of 9.2 hours on their professional job with a sample standard deviation of 5.1 hours. Calculate the specification hours with confidence of 95%.
3.In a set of 10 samples of bike, the mileage were listed as follows
41, 42, 45, 42, 47, 59, 55, 60, 40, 35
What percent of samples are getting more than 40 mileages?

Click here to see answer by stanbon(57984)

Question 173497: A sample of 20 pages was taken without replacement from the 1,591-page phone directory Ameritech Pages Plus Yellow Pages. On each page, the mean area devoted to display ads was measured (a display ad is a large block of multicolored illustrations, maps, and text). The data (in square millimeters) are shown below:
0
260
356
403
536
0
268
369
428
536

268
396
469
536
162
338
403
536
536
130
(a) Construct a 95 percent confidence interval for the true mean.b) Why might normality be an issue here?(c) What sample size would be needed to obtain an error of ±10 square millimeters with 99 percent confidence? (d) If this is not a reasonable requirement, suggest one that is.

Click here to see answer by Edwin McCravy(8999)

Question 173938: out of 35 programmers,25 knows FORTRAN, 28 knows pascal and 2 know neither. How many know both the languages?
Click here to see answer by josmiceli(9819)

Question 173939: out of 35 programmers,25 knows FORTRAN, 28 knows pascal and 2 know neither. How many know both the languages?
Click here to see answer by checkley77(12569)

Question 174117: if there are 13 books on the shelf and you choose 5 of them to line up on the second shelf how many different ways to line them up? order unimportant
Click here to see answer by checkley77(12569)

Question 174224: *finde the geometric mean of45,32,37,46,39,36,41,48,36
*

Click here to see answer by Mathtut(3670)

Question 174224: *finde the geometric mean of45,32,37,46,39,36,41,48,36
*

Click here to see answer by Edwin McCravy(8999)

Question 174301: compute the geometric and harmonic means for the following distribution of annual death rates:
xi[3.95,4.95,5.95,6.95,7.95,8.95,9.95,10.95,11.95,12.95,13.95]
Fi[1 ][ 4][5 ][13 ][12] [19] [13] [10] [6 ] [4 ] [ 1 ]

Click here to see answer by Edwin McCravy(8999)

Question 174340: 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 same day,would this prove that they are exceeding their goal, using α = .025?
Click here to see answer by Mathtut(3670)

Question 174363: The probability of rain is 20% on Friday,10% on Saturday,And 60% on Sunday.What is the probability that there is no rain on any of these three days?(To the nearest tenth of a percent).
Click here to see answer by stanbon(57984)

Question 174378: please help me with this question on probablity.
A bag Cantains 6 White and 4 black balls, two
balls are drawm at random. Find the probability
that they are one of the same colour:-
Thank you..
Click here to see answer by stanbon(57984)

Question 174375: Faced with rising fax costs, a firm issued a guideline that transmission of 10 pages or more
should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10
or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard deviation of 4.45 pages.
(a) At the .01 level of significance, is the true mean greater than 10? NO
(b) Use Excel to find the right-tail p-value.
(a) At the .01 level of significance, is the true mean greater than 10?

Click here to see answer by stanbon(57984)

Question 174374: A coin was flipped 60 times and came up heads 38 times.
(a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations.
(b) Calculate a p-value and interpret it.

Click here to see answer by stanbon(57984)

Question 174373: An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the average patient should pay no more than $250 out-of-pocket? State your hypotheses and decision rule. (b) Is this a close decision?
Click here to see answer by stanbon(57984)

Question 173598: Random sample of 120 customers’s spent an average of 9.2 hours on their professional job with a sample standard deviation of 5.1 hours. Calculate the specification hours with confidence of 95%.
Click here to see answer by stanbon(57984)

Question 174412: I've completed some of the questions - however I am not sure if they are correct. Your assistance with these 8 questions will be greatly appreciated.
Parametric and Nonparametric Data Identification Assignment
Label each of the following situations “P” if it is an example of parametric data or “NP” if it is an example of nonparametric data.
1. A manufacturer produces a batch of memory chips (RAM) and measures the mean-time-between-failures (MTBF). The manufacturer then changes a manufacturing process and produces another batch and again measures the MTBF. Did the change to the process improve the MTBF? _NP_
2. From a written survey where the respondents were asked to rate an individual on a scale of 1 to 5, one group rated an individual a 3.7, another group rated the individual a 4.3. Is the difference statistically significant? __P__
3. A catering company is buying equipment in order to set up their own store. They have a choice of two ovens that they can purchase for the store. The used oven is $100 less than the new oven, but its heating calibration is off by 20 degrees. Which one is a better buy for them? ____
4. Jim Smith owns three real estate offices in Anytown. He has decided to open one more office, but he cannot decide between Hometown or Uptown as the town where he wants to locate. He will be comparing the mean number of homes sold per real estate agent, and the mean commission percentage earned by agents in the two towns to make his decision. _P_
5. A study to determine if job absenteeism is distributed evenly over the week. _NP_
6. Mel’s Diner has been surveying their customers for the past couple of years about their dining experience in the restaurant. The survey uses a scale of one to five, five being best to indicate customer satisfaction. Mel’s customer satisfaction averaged 2.5 last year, but this year it is 2.9. Is this difference statistically significant? ____
7. Sally’s Beauty Salon just opened for business. Sally assigns the stylists customers on a rotation basis so that everyone is kept busy all day. One month after she opened the salon, Sally’s customer count for each stylist was (a) 20 customers; (b) 30 customers; (c) 15 customers; and (d) 25 customers. Has Sally been fair in how she allocates customers to each of the stylists? ____
8. A comparison of salaries between male and female employees in the same organization. _P__

Click here to see answer by stanbon(57984)

Question 173455: I am having difficulty with the following homework assignment. Could someone please check my answers and help? Thanks!
INSTRUCTIONS: Label each of the following situations “P” if it is an example of parametric data or “NP” if it is an example of nonparametric data.
1. A manufacturer produces a batch of memory chips (RAM) and measures the mean-time-between-failures (MTBF). The manufacturer then changes a manufacturing process and produces another batch and again measures the MTBF. Did the change to the process improve the MTBF? __P__
2. From a written survey where the respondents were asked to rate an individual on a scale of 1 to 5, one group rated an individual a 3.7, another group rated the individual a 4.3. Is the difference statistically significant? __NP__
3. A catering company is buying equipment in order to set up their own store. They have a choice of two ovens that they can purchase for the store. The used oven is $100 less than the new oven, but its heating calibration is off by 20 degrees. Which one is a better buy for them? __P__
4. Jim Smith owns three real estate offices in Anytown. He has decided to open one more office, but he cannot decide between Hometown or Uptown as the town where he wants to locate. He will be comparing the mean number of homes sold per real estate agent, and the mean commission percentage earned by agents in the two towns to make his decision. _P_
5. A study to determine if job absenteeism is distributed evenly over the week. _NP___
6. Mel’s Diner has been surveying their customers for the past couple of years about their dining experience in the restaurant. The survey uses a scale of one to five, five being best to indicate customer satisfaction. Mel’s customer satisfaction averaged 2.5 last year, but this year it is 2.9. Is this difference statistically significant? __NP__
7. Sally’s Beauty Salon just opened for business. Sally assigns the stylists customers on a rotation basis so that everyone is kept busy all day. One month after she opened the salon, Sally’s customer count for each stylist was (a) 20 customers; (b) 30 customers; (c) 15 customers; and (d) 25 customers. Has Sally been fair in how she allocates customers to each of the stylists? __P___
8. A comparison of salaries between male and female employees in the same organization. __P__

Click here to see answer by stanbon(57984)

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11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 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