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expressions/311367: SOLVE THE FORMULA FOR THE INDICATED VARIABLE. CHOOSE FROM THE FOLLOWING ANSWERS.
I=N/R+s for s
a. s=N+IR/I
b. s=N/I -R
c. s=N/I +R
d. s=R-IN/I 1 solutions
Answer 222703 by Fombitz(13828) on 2010-06-04 15:59:03 (Show Source):
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Human-and-algebraic-language/311363: Hi I am having a problem answering this question.
The sum of two numbers is -1. Five times the first number equals 3 times the second number. Find the two numbers.
Could you please help me find the answer and show me how to do it? Thanks 1 solutions
Answer 222697 by Fombitz(13828) on 2010-06-04 15:43:59 (Show Source):
You can put this solution on YOUR website!Let A and B be your numbers.
"sum of two numbers is -1"
1. 
"Five times the first number equals 3 times the second number"
2. 
From eq. 1,

Multiply both sides by 5,

Now substitute eq. 2 into eq. 1,

Then from eq. 2,
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Miscellaneous_Word_Problems/311195: You have administered a standardized test of manual dexterity to two groups of 10 semi skilled workers. One of these two groups of workers will be employed by you to work in a warehouse with many fragile items. The higher the manual dexterity of a worker the less likelihood that worker will break significant inventory. Because of a unique contract you must hire all 10 employees from one of the two groups and none of the employees from the other.
Group A Scores Group B Scores
99 78
100 86
60 79
59 92
95 75
97 86
67 90
34 59
81 79
96 64
You must decide which group to choose. Consider at least two measures of central tendency and at least one measure of dispersion for each group and use those to make your choice. Be sure to justify your choice with at least one page of discussion and analysis. Can you base a decision on the information provided and the measures that you calculated only?
1 solutions
Answer 222694 by Fombitz(13828) on 2010-06-04 15:33:34 (Show Source):
You can put this solution on YOUR website!Group A: Mean=78.8, St.Dev.=21.5
Group B: Mean=78.8, St.Dev.=10.1
The groups have the same mean, with Group A having more variability. CHoose Group B to lower the risk of breakage. They are more likely to have less overall breakage than Group A.
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Graphs/311264: Write in vertex form. Sketch a graph of the function and label its vertex.
1. y = x^2 + 4x - 7 1 solutions
Answer 222685 by Fombitz(13828) on 2010-06-04 15:12:45 (Show Source):
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Probability-and-statistics/311235: Air Transportation data from 1969-1998 collected from www.air-transport.org Assume it is a binomial distribution (fatal vs not fatal)
Year 1969 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88
Accidents 7 2 6 7 6 7 2 2 3 5 4 0 4 4 4 1 4 2 4 3
Year 1989 90 91 92 93 94 95 96 97 98
Accidents 8 6 4 4 1 4 2 3 3 0
a.) Find the mean and standard deviation of the number of fatal air travel accidents in 1997. There were 8 million flights.
b.) Could a person claim that 8 fatal crashes in a year are unusual? Explain. 1 solutions
Answer 222657 by Fombitz(13828) on 2010-06-04 13:55:07 (Show Source):
You can put this solution on YOUR website!The mean is 3.73, the standard deviation is 2.1.
A value of 8 would give you a z-score of 2.03, a little greater than 2 standard deviations from the mean. I guess "unusual" is in the eye of the beholder and it would depend on your level of concern regarding airline travel. I would feel better if the mean was lower and the standard deviation smaller but I wouldn't think that 8 was unusual based on the data.
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Probability-and-statistics/311251: A bowl contains only red and black marbles.There are x red marbles, with 2 more black marbles than red. If a marble is selected at random, what is the probability that it will be black?
a 2/x b x/(x+2) c x/(2x+2) d (x+2)/(2x+2) e 2/(x+2) 1 solutions
Answer 222655 by Fombitz(13828) on 2010-06-04 13:07:21 (Show Source):
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Probability-and-statistics/311184: Nigel keeps six CDs (Beatles, Duran Duran, Eminem, Five for Fighting, Gorillaz, and Styx) on a shelf in alphebetical order. If Nigel pulls them down and then puts them up in a random order, find the probability of P(Gorillaz CD is in the correct position). 1 solutions
Answer 222617 by Fombitz(13828) on 2010-06-04 10:24:37 (Show Source):
You can put this solution on YOUR website!There are 6 albums and 6 places to put them (with respect to each other).
That's 6! possible permutations.
Only one of them is correct.
P(correct order)=1/6!=1/720
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Equations/311194: Tripling the greater of two consecutive even intergers gives the same result as subtracting 10 from the lesser interger. What are the intergers? I do not understand how to work this problem can you help? 1 solutions
Answer 222615 by Fombitz(13828) on 2010-06-04 10:16:30 (Show Source):
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Linear-equations/311186: 3. Solve for X, Y, and Z in the following systems of three equations:
a. X + 2Y + Z = 22
X + Y = 15
3X + Y + Z = 37
b. 10X + Y + Z = 603
8X + 2Y + Z = 603
20X - 10Y - 2Z = -6
c. 22X + 5Y + 7Z = 12
10X + 3Y + 2Z = 5
9X + 2Y + 12Z = 14
1 solutions
Answer 222614 by Fombitz(13828) on 2010-06-04 10:14:32 (Show Source):
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Probability-and-statistics/311189: A bag contains 4 yellow,3 pink,2 red, and 1 blue marbles. A marble is drawn at random with replacement. Find each probability.
P(yellow,pink)
P(blue, blue)
P(red,pink,blue)
Thankyou 1 solutions
Answer 222612 by Fombitz(13828) on 2010-06-04 10:11:26 (Show Source):
You can put this solution on YOUR website!4 Y (yellow), 3 P (pink), 2 R (red), 1 B (blue)=10 total
.
.
.
P(Y)=4/10=2/5
P(P)=3/10
P(Y,P)=(2/5)(3/10)=3/25
.
.
.
P(B)=1/10
P(B,B)=(1/10)(1/10)=1/100
.
.
.
P(R)=2/10=1/5
P(P)=3/10
P(B)=1/10
P(R,P,B)=(1/5)(3/10)(1/10)=3/500
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Probability-and-statistics/311285: X P(x)
-1 .25
0 .15
1 .10
3 p
5 .10
7 .15
9 .05
What is the probability that x is 5?
What is the probability that x is no more than 5?
Expected Value of x=E(x)?
Variance?
Standard Deviation?
1 solutions
Answer 222607 by Fombitz(13828) on 2010-06-04 09:47:16 (Show Source):
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Probability-and-statistics/311230: You are generating pin codes for ATM cards. Each pin code has 5 places, and each place can be a small letter or a number between 0 and 9. No letter or number can be used more than once. How many different codes are there?
a) _10_ * _9_ * _8_ * _26_ * _25_ c) 26! + 10!
b) _36_ * _35_ * _34_ * _33_ * _32_ d) _35_ * _34_ * _33_ * _32_ * _31_
I thought the answer was d but i got it wrong can you explain why? 1 solutions
Answer 222606 by Fombitz(13828) on 2010-06-04 09:45:18 (Show Source):
You can put this solution on YOUR website!Your first place choice is out of 26 letters+10 numbers=36 total.
Then the second place is out of 35, since you cannot use the one you already chose.
Third, out of 34.
Fourth, out of 33.
Fifth, out of 32.

b) is the correct answer.
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