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edjones answered: 7568 problems
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1 solutions
Answer 317379 by edjones(7569)   on 2011-06-21 11:56:29 (Show Source):
You can put this solution on YOUR website!0 kids: n=122, mu[0]=7.42, s=3.92
1 kid: n=120, mu[1]=6.72, s=4.04
.
H[o]:mu[0]=mu[1]
H[a]:mu[0]<>mu[1]
.
z=(7.42-6.72)/0.257=2.72
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Since z=2.72 is in the rejection zone beyond 1.96 then the null hypothesis is rejected.
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Ed
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Proportions/462434: A man spends Rs 8100 in buying tables at Rs 1200 each and chairs at Rs 300 each.The ratio of the chairs to tables when maximum number of tables are purchased, is?
Options are
A. 1:4
B. 5:7
C. 1:2
D. 2:1
1 solutions
Answer 317051 by edjones(7569) on 2011-06-19 10:26:48 (Show Source):
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Miscellaneous_Word_Problems/462463: I submitted this question yesterday, but left out some vital information. Sorry! :-( Could I just blame it on age? Anyway, here we go again:
Three darts are thrown at the target shown below. Assume that each of the darts lands within one of the rings, or within the bull's eye. How many different point totals are possible?
Three rings- Outer ring - 3 points
Center ring - 4 points
Bull's eye - 9 points
Thanks for your patience.
1 solutions
Answer 317050 by edjones(7569) on 2011-06-19 10:19:41 (Show Source):
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Probability-and-statistics/462478: Hi, I have already sumitted this problem once, but havent gotten a reply, can someone help me?
a mini license plate for a toy car must consist of a number followed by two letters. Each letter must be a C, A, or R. each number must be a 3 or 7. repetition of letters is permitted.
.use the counting principle to determine the number of points in the sample space.
.construct a tree diagram to represent this situation.
.list the sample space.
.determine the exact probability of creating a mini license plate with a C. give solutions exactly in reduced fraction form.
1 solutions
Answer 317049 by edjones(7569) on 2011-06-19 10:12:41 (Show Source):
You can put this solution on YOUR website!Since "a mini license plate for a toy car MUST consist of a number followed by two letters" then the following are the only arrangements allowed for the letters:
CC, CA, CR, AC, RC, AA, AR, RA, RR The sample space.
There are 5 containing a C out of 9.
5/9 the exact probability of creating a mini license plate with a C.
.
Ed
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Probability-and-statistics/462483: I am trying hard to understand this stuff, but I am struggling, any help will be appreciated.
PERCENTILES: a union leader is told that, when all workers salaries are considered, the first quartile is $20,750. explain what that means.
1 solutions
Answer 317047 by edjones(7569) on 2011-06-19 09:55:54 (Show Source):
You can put this solution on YOUR website!Q[1] the first quartile is the 25th percentile. Remember quartiles and percentiles relate to the median, not the mean. Q[2], the 2nd quartile is the median. In order to use quartiles you must rank your data lowest 1st and highest last.
Ed
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Probability-and-statistics/462480: I appreciate all of the help you have given me, I was failing my math class until I found you. Can you help me with this problem.
Given that P(A)=0.4 AND P(B)=0.5 AND P(A AND B)=0.16 DETERMINE P(B|A).
1 solutions
Answer 317045 by edjones(7569) on 2011-06-19 09:31:46 (Show Source):
You can put this solution on YOUR website!P(B|A)
=P(A and B)/P(A) If you use a Venn diagram you will understand this and you dont have to memorize the formula.
=.16/.4
=.4
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Ed
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Proportions/462438: An amount of Rs 735 are divided among A,B and C.If each of them receives Rs 25 less,their shares would have been in the ratio 1:3:2.The money received by C was?
Options are
A. Rs 195
B. Rs 200
C. Rs 225
D. Rs 245
1 solutions
Answer 317042 by edjones(7569) on 2011-06-19 09:16:20 (Show Source):
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Probability-and-statistics/462317: There were 5 Multiple choice question with 4 possible answers to each on a history test. If you guessed on all of them, what's the probability that you got at least one question wrong?
A. 0.25
B. 1.25
C. 0.9990
D. .0009
E. 0.20
1 solutions
Answer 317010 by edjones(7569) on 2011-06-18 23:15:13 (Show Source):
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Probability-and-statistics/462397: 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?
1 solutions
Answer 317004 by edjones(7569) on 2011-06-18 22:59:05 (Show Source):
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Probability-and-statistics/462398: I am still having trouble trying to solve this problem. Everytime I do it I come up with a different answer. Can someone please show me how to go beyond this step?
8.In how many different ways can a committee of 9 members be chosen from
6 freshmen, 5 sophomores, and 4 juniors if the committee must consist of at least one freshman?
Ans:
#'s in the order of (frosh;soph;juniors)
The limits are 6 frosh;5 soph;4 juniors
1:5;3 (this means 1 frosh; 5 soph; 3 juniors): # of ways = 6*5*4C3 = 6*5*4 = 120
1;4;4::: # of ways = 6*5C4*4C4 = 30
1 solutions
Answer 317003 by edjones(7569) on 2011-06-18 22:55:11 (Show Source):
You can put this solution on YOUR website!If it must have one freshman so now we have a committee of 8 to choose from 14 students.
15C9=5005 ways with everyone.
9C9=1 way with no frosh.
5005-1=5004 different ways can a committee of 9 members be chosen from 6 freshmen, 5 sophomores, and 4 juniors if the committee must consist of at least one freshman.
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Ed
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Probability-and-statistics/462371: a card is selected from a deck of 52 playing cards. find the probability of selecting:
.an even number ten or less given the card is not a diamond.
.an ace, given that the card is black.
.a spade given the card is red.
show step by step work. give all solutions exactly in reduced fraction form.
1 solutions
Answer 316998 by edjones(7569) on 2011-06-18 22:30:52 (Show Source):
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Permutations/462383: In a shipment of 11 CD players, two are defective. Find the probability that a sample of 3 CD players will contain no more than one defective one.
1 solutions
Answer 316995 by edjones(7569) on 2011-06-18 22:23:42 (Show Source):
You can put this solution on YOUR website!(9C1*2C2)/11C3
=9/165 probability that sample contains 2 defective players.
1 - 9/165 = 156/165 the probability that a sample of 3 CD players will contain no more than one defective one.
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Ed
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Probability-and-statistics/462324: Jessica Salas, president of Salas Products, is reviewing the warranty policy for her company's new model of automobile batteries. Life tests performed on a sample of 100 batteries indicated: (1) an average life of 75 months, (2) a standard deviation of 5 months, and (3) a bell shaped battery life distribution. What percentage of the batteries will fail within the first 65 months of use?
1 solutions
Answer 316991 by edjones(7569) on 2011-06-18 22:10:29 (Show Source):
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Probability-and-statistics/462369: a parent can choose from 7 types of protein, 5 vegetables, and 3 desserts. If the parent serves a meal of 1 protein, 1 vegetable, and 1 dessert to the family, how many different meals can be served?
1 solutions
Answer 316979 by edjones(7569) on 2011-06-18 21:44:50 (Show Source):
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Probability-and-statistics/462373: Determine the critical region and critical values for z that would be used to test the null hypothesis at the given level of significance, as described in each of the following:
(A) Ho:u ≥ 81 and Ha: u < 81 , = 0.05
(B) Ho:u = 45 and Ha: u not equal 45, = 0.10
(C) Ho:u ≤ 88 and Ha: u >88, = 0.01
show all work
1 solutions
Answer 316978 by edjones(7569) on 2011-06-18 21:43:06 (Show Source):
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Probability-and-statistics/462372: a bag contains a total of 9 batteries, of which five are defective. selecting two at random, without replacement, determine the probability that none of the batteries you select are good.
1 solutions
Answer 316977 by edjones(7569) on 2011-06-18 21:34:18 (Show Source):
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Probability-and-statistics/462364: Consider the venn diagram below. Then numbers in the regions of the circle indicate the number of items that belong to that region.
THE CIRCLE A=40 THE CIRCLE B=80 AND THE SHARED REGION IS 10.
DETERMINE:
n(a)
n(b)
p(a)
p(b)
p(a/b)
p(b/a)
(the slash between the letters is meant to be a strait line.
THANK YOU ALL AGAIN FOR ALL OF YOUR HELP!
1 solutions
Answer 316975 by edjones(7569) on 2011-06-18 21:22:30 (Show Source):
You can put this solution on YOUR website!P(a)=40/(30+10+70)=4/11
P(b)=80/110=8/11
P(a|b)=10/80=1/8 Note: The "|" mark is on most computer keyboards. On mine it is above the "\" next to the square and curly brackets.
P(b|a)=10/40=1/4
I am not familiar with what n(a) and n(b) mean.
.
Ed
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Evaluation_Word_Problems/462347: Upon examining the contents of 38 backpacks, it was found that 23 contained a black pen, 27 contained a blue pen, and 21 contained a pencil, 15 contained both a black pen and a blue pen, 12 contained both a black pen and a pencil, 18 contained both a blue pen and a pencil, and 10 contained all three items. How many backpacks contained exactly two of the three writing instruments?
1 solutions
Answer 316974 by edjones(7569) on 2011-06-18 21:02:24 (Show Source):
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Probability-and-statistics/461973: Questions:
(1) In a group of 40 people at a party, what is the probability of at least two people having the same birthday. That is those who are born on the same day of the same month but not necessarily the same year. Assume 365 days in a year and no twins are present at the party.
(2) Bowl Cl contains 3 red and 7 blue chips and bowl C2 contains 8 red and 2 blue chips. All chips are identical in size and shape. A die is cast and bowl Cl is selected if five or six spots show on the side that is up; otherwise, bowl C2 is selected. The selected bowl is handed to another person and one chip is taken at random. Suppose that the selected chip is red, what is the probability the selected bowl was Cl?
(3) A jelly producer makes 7 types of jelly. the producer packages gift boxes containing 4 jars of jelly, no two are of the same type. to reflect the 3 national chains through which the jelly is distributed, the producer uses 3 types of boxes. How may different gift boxes are possible?
(4)A firm uses three machines to process its work. Machine A is the most heavily used machine, machine B is used twice as often as machine C and half as often as machine A.
If machine A produces a faultless product on 80% of occasions, machine B produces a faultless product on 70% of occasions and machine Closes 10% of its products to early faults, and of the product that remains, 90% is faultless. Find the probability that a faulty product ha..'l come from machine B.
(5) A manufacturing process requires the use of a robot welder on each of the 2 assembly lines, A & B, which produce 300 & 500 units of product per day, respectively. Based on past experiences, it is believed that the welder on A produces 2% defective units, whereas the welder on B produces 5% defective units. At the end of the day, a unit was selected at random from the total production and was found to be defective. WHat is the probability that it came from line A?
Thanks in advance.
1 solutions
Answer 316754 by edjones(7569) on 2011-06-17 09:30:53 (Show Source):
You can put this solution on YOUR website!2) Bowl Cl contains 3 red and 7 blue chips and bowl C2 contains 8 red and 2 blue chips. All chips are identical in size and shape. A die is cast and bowl Cl is selected if five or six spots show on the side that is up; otherwise, bowl C2 is selected. The selected bowl is handed to another person and one chip is taken at random. Suppose that the selected chip is red, what is the probability the selected bowl was Cl?
in three draws 3 + 8 + 8 = 19 total red chips, 2 eights because drawing that bowl is twice as likely.
3/19 the probability the selected bowl was Cl.
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Ed
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Probability-and-statistics/461577: Suppose that an insurance agent claims that less than 5% of his life insurance policies ever have to pay out. You decide to test his claim at the a=0.01 significance level. A sample of a 100 policies from last year finds that 7 out of them had to pay out. With a critical value of -2.33, compute the sample statistic. nora1.skelton@yahoo.com
1 solutions
Answer 316513 by edjones(7569) on 2011-06-16 01:44:01 (Show Source):
You can put this solution on YOUR website!H[o]:<.05
p[o]=.05, q[o]=.95, n=100
(P-p[o])/sqrt((p[o]*q[o])/n)
=(.07-.05)/sqrt((.05*.95)/100)
=.02/.022
=0.91 the sample statistic.
Since alpha for a 0.01 significance level is greater than 2.33 and the sample statistic is 0.91 then the null hypothesis in not is not rejected.
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Ed
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Probability-and-statistics/461528: A single 6-sided die is rolled twice.
A. Find the probability of getting 2 numbers whose sum is less than 5.
B. Find the probability of getting 2 numbers whose sum is greater than 5
C. Find the odds in favor of getting 2 numbers whose sum is greater than 5.
D. Find the odds against getting 2 numbers whose sum is greater than 5.
E. Find the probability of getting 2 numbers each of which is greater than 5.
1 solutions
Answer 316508 by edjones(7569) on 2011-06-16 01:12:30 (Show Source):
You can put this solution on YOUR website!A) 1/36 + 2/36 + 3/36 = 6/36 = 1/6
.
B) 5/36 + 6/36 + 5/36 + 4/36 + 3/36 + 2/36 + 1/36 = 26/36 = 13/18
.
C) 13/18 for success and 5/18 for failure or simply 13 to 5 in favor.
.
D) 5 to 13 are the odds against.
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E) two sixes = 1/6 * 1/6 = 1/36
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Ed
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Probability-and-statistics/461556: 1. A box contains 74 brass washers, 86 steel washers and 40 aluminum washers, Three washers are drawn at random from the box without replacement. Determine the probability that all three are steel washers.
1 solutions
Answer 316499 by edjones(7569) on 2011-06-16 00:26:06 (Show Source):
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