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Permutations/321026: how many different license plates could be made if the first two places on the license plate are letters that cannot be repeated and the last three places are numbers which can be repeated? 1 solutions
Answer 229916 by Fombitz(13828) on 2010-07-09 16:34:38 (Show Source):
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Probability-and-statistics/321023: The ages (in years) of seven people and the number of days they spent recovering in the hospital after surgery are given in the following table.
Age, x 12 21 38 44 59 63 70
Days in Hospital, y 4 6 7 5 9 11 12
Calculate the correlation coefficient, r.
1 solutions
Answer 229915 by Fombitz(13828) on 2010-07-09 16:32:18 (Show Source):
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Miscellaneous_Word_Problems/321015: I keep getting the wrong answer please help.
You are choosing between two health clubs. Club A offers a membership for a fee of $28 plus a monthly fee of $15.
Club B offers a membership for a fee of $24 plus a monthly fee of $16.
After how many months will the total cost of each health club be the same?
What will be the total cost for each club? 1 solutions
Answer 229899 by Fombitz(13828) on 2010-07-09 15:28:31 (Show Source):
You can put this solution on YOUR website!A: 
B: 
Set them equal to each other and solve for M.

Solve this equation to get M.
Once you solve for M, then use either equation to solve for cost.
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Graphs/320153: Graph the inequality on a plane
2x+3y is less than or equal to 6
Thank you 1 solutions
Answer 229897 by Fombitz(13828) on 2010-07-09 15:24:55 (Show Source):
You can put this solution on YOUR website!

.
.
.
Graph the line  ,
.
.
.

.
.
.
Choose a point not on the line and test the inequality.
(0,0) is a good choice.

True, (0,0) is in the solution region.
Shade the region containing (0,0) including the line.
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Sequences-and-series/319907: Given these sets:
A = {1, 2, 3, 4}
B = {3, 4, 5, 6, 7}
C = {3, 5, 7, 9}
List the elements of this set
B(A∩C) 1 solutions
Answer 229887 by Fombitz(13828) on 2010-07-09 14:55:26 (Show Source):
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Quadratic_Equations/321012: Complex Fraction: Problem type 2
Simplify as much as possible
w_____
w+5w
_______
1+4
_____
w+1 1 solutions
Answer 229886 by Fombitz(13828) on 2010-07-09 14:53:27 (Show Source):
You can put this solution on YOUR website!Could you please re-write your fraction?
Don't try to make it visually appealing.
Use parentheses to remove any doubts.
Example,
w/(5+w)= 
(1+4/(w+1))= 
Did you mean like this?
(w/(5+w))/(1+4/(w+1))= 
OK Here goes!
.
.
.

Dividing by a fraction is the same as multiplying by it's reciprocal.
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Polynomials-and-rational-expressions/319919: The profit P (in dollars) generated by selling x units of a certain commodity is given by P(x) = -1500 +12x-0.0004x^2
a. What is the maximum profit?
B. How many units must be sold to generate it? 1 solutions
Answer 229883 by Fombitz(13828) on 2010-07-09 14:45:14 (Show Source):
You can put this solution on YOUR website!You can find the max. value by putting the equation into vertex form,  , by completing the square.
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.
.

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The minimum occurs at the vertex.
a) 
b)  at  :
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Percentage-and-ratio-word-problems/321004: The mathematics faculty at a college consists of 4 professors, 7 associate professors, 6 assistant professors,and 9 instructors. If one faculty member is randomly selected, find the probability of choosing a professor or an instructor.
The probability is:
(fraction/simplified answer)
Thank you! 1 solutions
Answer 229879 by Fombitz(13828) on 2010-07-09 14:22:35 (Show Source):
You can put this solution on YOUR website!4 P-professors,
7 A-associate professors
6 S-assistant professors
9 I-instructors
26 total
P(P)= 
P(I)= 
P(P or I)=P(P)+P(I)
P(P or I)=
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