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Inequalities/327127: Find and Graph the solution set.
a. x^3-16x>0
b. x^2-5x<=-6 1 solutions
Answer 234332 by Fombitz(13828) on 2010-07-30 15:53:45 (Show Source):
You can put this solution on YOUR website!

Break up the number line into 4 regions:
Region 1 : (  ,  )
Region 2 : (  ,  )
Region 3 : (  ,  )
Region 4 : (  ,  )
Choose a point in the region (not an endpoint).
Test the inequality.
If the inequality is satisfied, the region is part of the solution.
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Region 1:

False, this region is not part of the solution.
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Region 2:

True, this region is part of the solution.
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Region 3:

False, this region is not part of the solution.
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Region 4:

True, this region is part of the solution.
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The solution region is (  ,  ) U (  ,  ).
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Verified graphically
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Similarly,

Break up the number line into 3 regions:
Region 1 : (  ,  )
Region 2 : (  ,  )
Region 3 : (  ,  )
Choose a point in the region (not an endpoint).
Test the inequality.
If the inequality is satisfied, the region is part of the solution.
.
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.
Region 1:

True, this region is part of the solution.
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Region 1:

False, this region is not part of the solution.
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Region 2:

True, this region is part of the solution.
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Region 3:

False, this region is not part of the solution.
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The solution region is [  ,  ].
Since the inequality includes the "=" the brackets denote that 2 and 3 are included as part of the solution.
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Equations/327194: please solve this: 50/5x10-6x2+8= 1 solutions
Answer 234329 by Fombitz(13828) on 2010-07-30 15:22:55 (Show Source):
You can put this solution on YOUR website!You can't solve it unless there is something after the "=".
If not it's just an expression.
You can simplify an expression, but you can't solve it.
If that's what you're looking for then
 is in its simplest form because it is not factorable.
In addition all of the solutions of  are complex.
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Probability-and-statistics/327173: The measure of the length of the index finger of a human right hand is normally distributed with a mean of 6cm and a standard deviation of 0.5cm What is the probability that the index finger length of a randomly selected person will between 5cm and 7.5cm?
a) .9759 b) .0241 c) .95 d) 1.0 e) none of the above
Please show work so i can understand 1 solutions
Answer 234322 by Fombitz(13828) on 2010-07-30 15:01:17 (Show Source):
You can put this solution on YOUR website!Find the z-score for each,

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Find P(z1) and P(z2).

To find the probability for the range, subtract.

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a) is the correct answer.
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Probability-and-statistics/327037: Twelve $5-bills, eight $10-bills, and five $20-bills are put into a bag and shaken up. You get to reach in and pull out two of the bills without looking. What is the probability you get a total of at least $20?
a 46% b 54% c 66 2/3% d 33 1/3% e 60%
1 solutions
Answer 234303 by Fombitz(13828) on 2010-07-30 13:32:11 (Show Source):
You can put this solution on YOUR website!12 $5, 8 $10, 5 $20=25 bills total
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Remember for the second probability, the total number of bills is reduced by 1.
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 
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If you add all of these probabilities together, you will get  , since these outcomes represent all of the possible outcomes.
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Now find, the ones that sum to at least $20 and add up their probabilities.
3,5,6,7,8,9 all sum to at least $20. Add up all of their probabilities or you could add 1,2, and 4 probabilities and subtract from 1.
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P(>=$20)=  or 46%
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Equations/327099: list the three terms which complete the sequence and then classify as arithmitic, geometric or neither:
100,000 ,50,000 , 25,000 , ______,__________,_________ 1 solutions
Answer 234285 by Fombitz(13828) on 2010-07-30 13:13:39 (Show Source):
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Probability-and-statistics/327124: 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
THE ANSWER IS 0.06.....BUT THE CHOICES ARE DIFFERENT SO HOW DO I ANSWER IT PLEAAAASE.
1 solutions
Answer 234282 by Fombitz(13828) on 2010-07-30 13:08:39 (Show Source):
You can put this solution on YOUR website!The answer is 0.06 but the answer is not any of the choices.
I'm confused.
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They are independent
P(A or B)= 
P(A and B)=P(A then B)=P(B then A)=
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Probability-and-statistics/327123: a roulette wheel has 38 slots in which the ball can land. two of the slots are
green, 18 are red, 18 are black. the ball is equally likely to land in any slot.
the roulette wheel is going to be spun twice and the outcome of the two spins
are independant.
the probability that it lands on red the first time and black the second time
is:
a- 0.2136
b- 0.2244
c- 0.2500
d- 0.5000
PLEASE HELP
1 solutions
Answer 234280 by Fombitz(13828) on 2010-07-30 13:03:09 (Show Source):
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logarithm/327063: Express as a sum, difference, and product of logarithms, without using exponents
logb 4 square root of ((x^5b^9)/(y^7z^10))
a: 5/4 logb x+9-7logb y-10logb z
b: 5/4 logb x+ 9/4-7/4 logb y-5/2 logb z
c: 1/4 (logb x^5+logb b^9- logb y^7 +logb z^10)
d: 5/4 logb x+9/4 -7/4 logb y+ 5/2 logb z 1 solutions
Answer 234264 by Fombitz(13828) on 2010-07-30 11:03:49 (Show Source):
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Miscellaneous_Word_Problems/327081: A bag contains 16 yellow marbles, 6 green marbles, and 7 red marbles. What is the chance of drawing a yellow marble? If a yellow marble is drawn the first time and then a secong marble is drawn without replacement, what is the probability of drawing a second yellow marble? 1 solutions
Answer 234256 by Fombitz(13828) on 2010-07-30 10:51:48 (Show Source):
You can put this solution on YOUR website!16 Yellow
6 Green
7 Red
29 Total
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1. 
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2. 
Without replacement, the number of yellow marbles and total marbles drops by one,

P(both yellow)=
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