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Miscellaneous_Word_Problems/359050: The table below shows the customer rating of five restaurants in the metro city guide to restaurants. The rating scale is from 1 ,the worst ,to 10, the best . which of the five restaurants has the best average rating ?
Restaurant food décor service value
Del 7 9 4 7
Aqua 8 9 4 6
Le 10 8 3 5
Sushi 7 7 5 6
Metro 9 8 7 7
A metro B le C aqua D sushi 1 solutions
Answer 256233 by Fombitz(13828) on 2010-10-20 09:41:16 (Show Source):
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Probability-and-statistics/359044: compute the mean, mode, range, standard deviation and variance from the following set of scores: 145, 210, 300, 178, 110, 237, 155, 187, 204, 205, 205, 287, 256, 200 1 solutions
Answer 256224 by Fombitz(13828) on 2010-10-20 09:24:30 (Show Source):
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Rate-of-work-word-problems/359042: I am not sure how to begin setting this equation up. I know that it requires the d=r*t formula but what goes where and how do I solve it?
Filling a tank. A water tank has an inlet pipe and a drain
pipe. A full tank can be emptied in 30 minutes if the drain
is opened and an empty tank can be filled in 45 minutes
with the inlet pipe opened. If both pipes are accidentally
opened when the tank is full, then how long will it take to
empty the tank? 1 solutions
Answer 256220 by Fombitz(13828) on 2010-10-20 09:18:00 (Show Source):
You can put this solution on YOUR website!Rate*Time=Volume
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.
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Let the pool volume be  .
Calculate the fill rate,

Calculate the drain rate,

Calculate the time when both valves are open,

Substituting,
 minutes
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Miscellaneous_Word_Problems/358989: A Math quiz has 25 questions. A correct answer earns 8 points, and a wrong one
costs 3 points. Jess scores 110 points. How many questions does Jess answer? 1 solutions
Answer 256217 by Fombitz(13828) on 2010-10-20 09:10:05 (Show Source):
You can put this solution on YOUR website!Let R be the number of right answers, W for wrong answers.
1. 
2. 
Multiply eq. 1 by 3 and add to eq. 2 to eliminate W.

Something is wrong with the problem setup since 11 is not a factor of 185, you won't get an integer answer for  as required.
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17 right, 8 wrong would give Jess 112 points.
16 right, 9 wrong would give Jess 101 points.
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Quadratic_Equations/359025: Solve
1) The solution set is????
"use at least one inequality or compund inequality to express your answer"
Please help me 1 solutions
Answer 256210 by Fombitz(13828) on 2010-10-20 09:00:27 (Show Source):
You can put this solution on YOUR website!
Break up the number line into 4 regions using the critical points of the function.
Region 1:(  ,  )
Region 2:(  ,  )
Region 3:(  ,  )
Region 4:(  ,  )
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.
.
For each region, choose a point in the region (not an endpoint).
Test the inequality.
If the inequality is satisfied, the region is part of the solution region.
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.
Region 1:

False, Region 1 is not part of the solution region.
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.
Region 2:

True, Region 2 is part of the solution region.
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.
Region 3:

False, Region 3 is not part of the solution region.
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.
Region 4:

True, Region 4 is part of the solution region.
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Solution Region: (  ,  ) U (  ,  )
or
(  ) and (  )
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Graphical verification: Look for regions where the function is above the x-axis (  )
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Probability-and-statistics/359027: Could someone explain this to me because the book was no help.
The random variable x has the following probability distribution:
x 1 2 3 4 5
___________________________________________________
P(x) 0.6 0.1 0.1 0.1 0.1
a.) Find the mean and standard deviation of x.
b). What is the probability that x is between mean - standard deviation and mean + standard deviation?
1 solutions
Answer 256204 by Fombitz(13828) on 2010-10-20 08:52:10 (Show Source):
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Quadratic_Equations/359024: For the following equation, state the value of the discriminant and then describe the nature of the solutions.
1) what is the value of the discriminant???
2) Does the equation have one real solution, two real solutions, or two imaginary solutions???
Really lost please help me 1 solutions
Answer 256201 by Fombitz(13828) on 2010-10-20 08:40:13 (Show Source):
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Rational-functions/358803: Given the following 3 points, find the particular equation. Graph the parabola. Label the axis of symmetry, vertex, y-intercept and its symmetric partner, and the x-intercepts.
(3,138) (10, 292) (15, 282) 1 solutions
Answer 256196 by Fombitz(13828) on 2010-10-20 08:28:19 (Show Source):
You can put this solution on YOUR website!
.
.
.

1. 
.
.

2. 
.
.

3. 
Subtract eq. 1 from eq. 2 to eliminate  ,

4. 
Subtract eq. 1 from eq. 3 to eliminate  ,

5. 
Subtract eq. 4 from eq. 5 to eliminate

Then,

Then,

.
.

.
.
Convert to vertex form,  , by completing the square.

The vertex is (  ,  ).
.
.
The vertex lies on the axis of symmetry  .
.
.
The y-intercept is,

Its symmetric partner would be

(  ,  )
.
.
The x-intercepts are,

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.
.
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