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Answer 261342 by robertb(4012) on 2010-11-05 21:21:34 (Show Source):
You can put this solution on YOUR website!Probability of Type I error = 1 - Confidence Level. For example, assigning a confidence level of 95% means you're only giving yourself 1 - 0.95 =0.05, or 5% chance of making a type I error, that is, a 5% window of making the mistake of rejecting the null hypothesis (status quo) when it is actually true.
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Probability-and-statistics/366576: This is two questions I am having an issue with. The only two I cannot figure out. I really would appreciate it if there was a way you could scan the page back and upload it completed and how you did it? Thank you
Here is the uploaded page with 2 questions:
http://img525.imageshack.us/img525/2033/ccf1105201000000.jpg 1 solutions
Answer 261338 by robertb(4012) on 2010-11-05 21:10:37 (Show Source):
You can put this solution on YOUR website!Hmm. Get back to you soon. Got a class to teach.
Back now.
14.
a.)  . This corresponds to the open interval (0.39404, 0.45962).
b.) No, it is not reasonable to conclude from the sample that the president is doing a good job. In fact we could say that the true proportion may be less than 50%. (As opposed to the null hypothesis that the true proportion is equal to or greater than 50%.)
15.
a.) $63/hr.
b.) Using the t-distribution with 22 degrees of freedom, the C.I. is  . This corresponds to the open interval (59.81, 66.19).
c.)We use the standard normal table again. We want  . This should give  , or  . We can put n = 101.
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Probability-and-statistics/366687: Why does the significance level differ among industries? Is the null hypothesis more likely to be rejected at α = 0.01 than α = 0.10? As the significance level increases to α = 0.10 from α = 0.01, which type error is more likely to occur? 7What may be done to reduce the likelihood of incurring this error?
1 solutions
Answer 261325 by robertb(4012) on 2010-11-05 20:47:16 (Show Source):
You can put this solution on YOUR website!Significance levels differ among industries because different industries hold different quality standards. The null hypothesis is more likely to be rejected at 0.10 significance level. As the significance level increases to α = 0.10 from α = 0.01, type I error is more likely to occur (that is, it is more likely that we reject a statement that may actually be true.) To reduce the likelihood of a type I error, continuous and periodic sampling within the industry is suggested (quality control) using as large (but manageble)a size as possible.
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Linear-systems/366585: system of four linear algebraic equation (get values of A,B, C and D)
0= Acos(t)+Bsin(t)+Ctcos(t)+Dtsin(t)+3t-2
0=-Asin(t)+Bcos(t)+Ccos(t)-Ctsin(t)+Dsin(t)+Dtcos(t)+3
1=-Acos(t)-Bsin(t)-2Csin(t)-Ctcos(t)+2Dcos(t)-Dtsin(t)
1= Asin(t)-Bcos(t)-2Ccos(t)-Ccos(t)+Ctsin(t)-2Dsin(t)-Dsin(t)-Dtcos(t) 1 solutions
Answer 261324 by robertb(4012) on 2010-11-05 20:36:36 (Show Source):
You can put this solution on YOUR website!Let t = 0. Then the system becomes
0 = A-2,
0 = B+C+3,
1 = -A+2D,
1 = -B-2C-C, or 1 = -B - 3C.
The 1st equation gives A = 2.
Substitution into the 3rd equation gives 1 = -2 + 2D, or D = 3/2.
eliminating B from the 2nd and 4th equations gives C = 1.
Finally, substitution into the 2nd equation gives B=-4.
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Exponential-and-logarithmic-functions/366682: My child is having trouble with Real exponents and exponential functions, and I don't understand how to do it in order to help her.
Problem: 13 square root6 * 13 square root 24 =
I don't know how to put square root on computor, sorry 1 solutions
Answer 261319 by robertb(4012) on 2010-11-05 20:19:21 (Show Source):
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Mixture_Word_Problems/366644: How many gallons of pure water must be added to 10 gallons of 30% saltwater to make a solution that is 25% saltwater?" 1 solutions
Answer 261294 by robertb(4012) on 2010-11-05 18:23:45 (Show Source):
You can put this solution on YOUR website!let x = # gallons pure water that must be added. Then
10*0.30 + x*0.00 = (10 + x)0.25,
3 = 2.5 + 0.25x,
0.5 = 0.25x
x = 2 gallons of water must be added.
***Note: x*0.00 denotes the weight contribution of the water to the salt content of the newly mixed solution. x is in gallons, and its salt concentration is 0.00 weight units per gallon, so that x*0.00 is in weight units.***
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Functions/366461: How do I solve the following to THREE decimal places?
ln x + ln(x+7) = -5 1 solutions
Answer 261149 by robertb(4012) on 2010-11-05 07:01:16 (Show Source):
You can put this solution on YOUR website!
 ,
Hence  , or  . Using the quadratic formula:
 . The values are, to 3 decimal places, 0.001 (from 0.000962432), or -7.0001 (from -7.000962432). We have to eliminate the 2nd value, because it won't satisfy the original equation. The answer is 0.001.
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Functions/366460: how do i find the domain of f(x)=2-ln(7x)?
and the domain of f(x)=log(4)(x-4)^2?
I am struggling with these....typical for someone out of math for 25 years. 1 solutions
Answer 261146 by robertb(4012) on 2010-11-05 06:49:17 (Show Source):
You can put this solution on YOUR website!For the first function must make sure that 7x >0, or x>0 (after dividing both sides of the inequality by 7).
For the second function,  . This is just the set of all real numbers except x = 4.
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Probability-and-statistics/366318: The length of a Colorado brook trout is normally distributed. What is the probability that a brook trout’s length:a.) exceeds the mean?b.) exceeds the mean by at least 1 standard deviation?c.) exceeds the mean by at least 2 standard deviations?d.) is within 2 standard deviations? 1 solutions
Answer 261142 by robertb(4012) on 2010-11-05 06:35:20 (Show Source):
You can put this solution on YOUR website!By the property of a normal distribution, the probability that a brook trout's length a.)exceeds the mean is 0.50,
b.) exceeds the mean by at least 1 standard deviation is about 0.16 (by adjusting the 68-95-99.7 rule),
c.)exceeds the mean by at least 2 standard deviations is about 0.025(by adjusting the 68-95-99.7 rule),
d.)is within 2 sd's is 0.95.
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Functions/366308: I am in the process of learning these things and a way to make it more interesting besides the ol' make it into a word problem thing. Can you help me 1 solutions
Answer 261138 by robertb(4012) on 2010-11-05 06:21:27 (Show Source):
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Probability-and-statistics/366449: In a game, there are three rounds; the probabilities of winning first, second & third rounds are 3/4 , 1/2 and 1/4 respectively. A prize will be given, if any one wins all the rounds. What is the probability of winning the prize?
A. 29/32 B. 1/32 C. 9/32 D. 3/32 E. none 1 solutions
Answer 261136 by robertb(4012) on 2010-11-05 06:20:19 (Show Source):
You can put this solution on YOUR website!Assuming the 3 events are mutually independent (i.e., performance in the next round is not affected by the previous round), the probability is  . The answer is D.
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Probability-and-statistics/366456: SUPPOSE that X Is a discrete random variable with p(X+0)=.25,P(X+2)=.125 AND P(X=3)=.5.PLOT THE PROBABILITY MASS FUNCTION AND CUMULATIVE DISTRUTION FUNCTION OF X.
1 solutions
Answer 261134 by robertb(4012) on 2010-11-05 06:14:34 (Show Source):
You can put this solution on YOUR website!I got a feeling you meant the following:
p(X=0)=.25,
P(X=1)=.125
P(X=2)=.125 and
P(X=3)=.5, right?
The cumulative distribution function is
F(X = 0) = 0.25
F(X = 1) = 0.375
F(X = 2) = 0.5
F(X = 3) = 1.
It's easy to plot the probability mass function for this distribution.
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Permutations/366458: Using permutations, how do we solve this problem: How many distinguishable 6 letter "words" can be formed using the letters in LONDON? the answer is 180, but I can't figure out how to solve it. Please help. 1 solutions
Answer 261132 by robertb(4012) on 2010-11-05 06:08:06 (Show Source):
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