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MathLover1 answered: 6636 problems
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Functions/694712: Is this a function: {(x.y) | x^2 +(y-1)^2 = 4} 1 solutions
Answer 428183 by MathLover1(6638) on 2012-12-16 11:50:11 (Show Source):
You can put this solution on YOUR website!{(x.y) |  }
What is a  ?
A  relates   to   .
A  is a  that assigns  to a member of   , a member of the  set. The key word is "  ".
So if you assign say  as well as  to number  , then you  a  , but  a  . That is the logic behind the    . If you draw a vertical line and it intersects the graph of the function in    , then you can see that it means you have assigned both of these points to the point where your vertical line  the  .
An example of this is the  , and you have a  .
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Graphs/694619: I am having trouble solving the relationship between x and f(x) for the following
input output
-1 3
0 2
1 1 1 solutions
Answer 428079 by MathLover1(6638) on 2012-12-15 18:46:42 (Show Source):
You can put this solution on YOUR website!the relationship between  and  for the following
 or
given:
input output
 ...........  or
so, you are given three points which you can plot on a Cartesian coordinate system and graph a line that contains these points
(  ,  )= (  ,  )
(  ,  )= (  ,  )...this is
(  ,  )= (  ,  )
now we can find the equation of a line passing through these points
| Solved by pluggable solver: FIND EQUATION of straight line given 2 points |
hahaWe are trying to find equation of form y=ax+b, where a is slope, and b is intercept, which passes through points (x1, y1) = (1, 1) and (x2, y2) = (0, 2).
Slope a is .
Intercept is found from equation , or . From that,
intercept b is , or .
y=(-1)x + (2)
Your graph:

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so,the equation of a line passing through these points is  where  and
now we can check if all three given points lie on this line
as you can see, all three given points do lie on this line
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Probability-and-statistics/694369: Find each probability
a. P(5;4)
b. P(2;4)
c. P(6;3)
d. P(10;7)
e. P(9;8)
Part 2
A copy machine randomly puts out 10 blank sheets per 500 copies processed. Find the probability that in a run of 300 copies, 5 sheets of paper will be blank.
Part 3
A recent study of robberies for a certain geographic region showed an average of 1 robbery per 20,000 people. In a city of 80,000 people, find the probability of the following:
a. 0 robberies
b. 1 robbery
c. 2 robberies
d. 3 or more robberies
part 4.
In a 400 page manuscript, there are 200 randomly distributed misprints. If a page is selected, find the probability that it has 1 misprint. 1 solutions
Answer 427900 by MathLover1(6638) on 2012-12-14 18:17:25 (Show Source):
You can put this solution on YOUR website!1.
Probability of event  that occurs:
Probability of event  that does not occur:
 (  ') =
 (  ') =
 (  ')=
2.
A copy machine randomly puts out 10 blank sheets per 500 copies processed.
the probability that in a run of  copies,  sheets of paper will be blank is
 ≈
3.
The Binomial distribution has the probability
function
 =  ,  ,  ,.....,
where
For  people, we expect  robberies.
a)
use the source to compute
Using Poisson with
b)
Using Poisson with lambda=4
c)
d)
p( highlight(x >=3))= p( 3 through 20000)
This uses normal approximation instead of Binomial because  is too large and  is too small.
4.
Presuming there are  of  total pages with misprints, there is a  % probability of discovering one on any given page.
 which is  %
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Probability-and-statistics/694295: The sum of the probabilities of complementary events is equal to 1.
Choose one answer.
a. True
b. False
Question 3
Marks: 3
Thirty people were asked about their favorite color, 10 said red, 15 said green, and 5 said blue. What is the probability that a person chosen has a favorite color of red or blue?
Choose one answer.
a. 50%
b. 83%
c. 33%
d. 67%
1 solutions
Answer 427829 by MathLover1(6638) on 2012-12-14 11:11:31 (Show Source):
You can put this solution on YOUR website!1.
answer:
a.
The sum of the probabilities of complementary events is  .
P(A) + P(A') =
2.
answer is: a.  %
if  red,the probability a person chosen has a favorite color of red is
and if  blue, the probability a person chosen has a favorite color of blue is
so, the probability a person chosen has a favorite color of red and blue is  ≈  or  %
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Surface-area/694290: slant height of frustum of cone is 5cm .if difference between radius of its two circular ends is 4cm .write the height of frustum.
1 solutions
Answer 427820 by MathLover1(6638) on 2012-12-14 09:27:22 (Show Source):
You can put this solution on YOUR website!
make a sketch of its cross section and draw in the height
I see a right -angled triangle with height h, so that
 ...where  and  are  of the base,  is  , and  is
given:
the difference between radius of its two circular ends is
 ....plug in given values
as you can see, the infamous  right-angled triangle
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Triangles/694162: In a triangle, angle A is 60 percent of angle C, and angle B is 150 percent of angle A.
How many degrees does the smallest angle of the triangle measure? 1 solutions
Answer 427766 by MathLover1(6638) on 2012-12-13 21:06:08 (Show Source):
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Graphs/693896: What is the slope of the line passing through the points (2, 5) and (0, -4? 1 solutions
Answer 427617 by MathLover1(6638) on 2012-12-13 12:09:32 (Show Source):
You can put this solution on YOUR website!
| Solved by pluggable solver: FIND EQUATION of straight line given 2 points |
hahaWe are trying to find equation of form y=ax+b, where a is slope, and b is intercept, which passes through points (x1, y1) = (2, 5) and (x2, y2) = (0, -4).
Slope a is .
Intercept is found from equation , or . From that,
intercept b is , or .
y=(4.5)x + (-4)
Your graph:

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Money_Word_Problems/693846: How much simple interest would be paid on a loan of $2720 at 14% for 3 years? 1 solutions
Answer 427580 by MathLover1(6638) on 2012-12-13 09:18:00 (Show Source):
You can put this solution on YOUR website!
Simple interest is calculated on the original principal only.
where:
 = principal (original amount borrowed or loaned)
 = interest rate for one period
 = number of periods
so, if you have a loan of $  at  % annually for  years, you will pay:
$
$
$
$
$
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Angles/693845: How to calculate complementary angle of 20 degree 5 minute.
If i subtract 90 degree - 20 degree 5 minute
i get 89 degree 60 minute - 20 degree 50 minute
= 69 degree 10 minute.
But ans should be 69 degree 5 minute. How to get this. Please help. 1 solutions
Answer 427578 by MathLover1(6638) on 2012-12-13 09:05:55 (Show Source):
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Expressions-with-variables/693317: I have a question about elimination i have alot of trouble doing it and i need help understanding whats its used for and how its different from substitutions. it would be really great if you could help thank. sincerly,user 1 solutions
Answer 427355 by MathLover1(6638) on 2012-12-12 09:19:01 (Show Source):
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Circles/692844: A pleasant day Sir/ Madam, my daughter has this problem in geometry and I am not good in geometric proofs, can you please help me?
the illustration or drawing is a rectangle inscribed in a circle
Given: Quadrilateral ABCD is a rectangle
Prove: line segment AC and line segment BD are diameters of the circle
Thank you very much for anyone who can help me! 1 solutions
Answer 427124 by MathLover1(6638) on 2012-12-11 13:12:06 (Show Source):
You can put this solution on YOUR website!
first draw the picture:
next, we will need to prove this:
theorem: Diagonal of any rectangle inscribed in a circle is a diameter of the circle. (
This is essentially the converse of Thales' theorem.
Let A, B, C and D be the vertices of a rectangle inscribed in a circle and let AC and BD be the diagonals of this rectangle.
We can now focus on any one of the four triangles:
 ,  ,  and
Let's take  :
 side of this triangle is the  of the rectangle
 and  are two sides of the rectangle, which potentially may be of different length (but we will prove they must be the  if the area of the inscribed rectangle is maximized).
The angle at  is the right angle since it is one of the angles of the rectangle, which by definition has four right angles.
Hence, looking at the triangle  , we can see that this is a  triangle inscribed in the circle.
Therefore to prove (1), we need to show that side  of any such triangle must be a diameter of circle.
Proof:
Choose any three points  ,  and  on the circle and connect these points to make a triangle  .
Let's suppose that the claim is that the angle at  is right angle.
We will show that if this is true then it must follow that  is a  of the  .
Connect the center of the circle (  ) with each of the vertices of the triangle creating the segments  ,  and  .
Let's call the angle defined by the path  as  and the angle defined by the path  as  .
Since  ,  and  are all of  length (equal to the length of the radius of the circle ) then     (  ,  and  ) are  .
We will next want to find the angle between  and  (the angle at  made out by segments  and  ) using only angles  and  as given.
The angle between  and  is equal to  ° (due to the fact that  is  and the fact that the sum of all three internal angles in a triangle sum to  °).
Similarly, the angle between  and  is equal to  °.
Finally, since all the three angles at  add up to  ° (full circle), it follows that the angle between  and  is equal to  .
However, the angle at  of the original triangle  is equal to  (follows from the fact that  and  triangles are  ).
This angle was claimed to be  ° and therefore the angle between  and  is equal to  °.
This means that the points  and  and the  of the circle (  ) are  .
In other words, the  of the circle is  on the straight line segment  , which in turn means that   be a  of the  .
So, we can conclude that   of the rectangle inscribed in a circle  be a circles  .
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Graphs/692801: determine the point of intersection of:
a) 1/2(x-2)-1/4(3-y) ≥ 2
3x-4y ≥ 2
b) x-3(y-3) ≤ 3
2x - 1/3(3-3y) ≥ 4
x + 5/3y ≥ 1 1 solutions
Answer 427102 by MathLover1(6638) on 2012-12-11 10:14:09 (Show Source):
You can put this solution on YOUR website!a)
_________________
first graph both lines as  and  , find  and  and find intersection point
 ...set  and find
 ........=>.........  ;  is at (  ,  )
 ...set  and find
 ........=>....  =>....  ;  is at (  ,  )
--
 ...set  and find
 ........=>.........  ;  is at (  ,  )
 ...set  and find
 ........=>....  =>....  ;  is at (  ,  )
draw a lines, note both of them are a part of solution
now shade the part where  and
b)
do same with these inequalities
 ....=>...  =>...  =>...  ...=>...  ...=>...
 ..=>..  ..=>..  ..=>..  ..=>..
 ...=>...  ...=>...  ..=>...
same way you find  and  and draw a lines than shade the area that belongs to a solution ; it will look like this:
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