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Answer 250248 by Fombitz(13828) on 2010-09-30 10:17:39 (Show Source):
You can put this solution on YOUR website!You can't write it on a number line.
Anyways, 4 is not less than 1.
4 is greater than 1 as shown on the number line.
Values to the left of a number are smaller than the number on a number line.
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Coordinate-system/350008: The profit earned from manufacturing x widgets is .0001x^3 - .21x^2 + 135x - 2000 dollars. Other contraints dictate that at least 200 widegets but no more than 950 widgets be manufactured.
Use your graphing calculator to determine how many widgets should be produced to earn the maximum profit. 1 solutions
Answer 250246 by Fombitz(13828) on 2010-09-30 10:12:18 (Show Source):
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test/350019: Please help me solve this equation: Find a vertical line x=a that bisects the region bounded by the curve , the x-axis and between x=1 and x=8. 1 solutions
Answer 250239 by Fombitz(13828) on 2010-09-30 09:56:47 (Show Source):
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Quadratic_Equations/350123: i started this question however am unsure if it is correct question: √((a+4)²)
since we are looking for the square root of (a+4)^2 i would think that the answer is just a+4 because squaring it would be a^2+4^2 and the square root of that would be a+4
1 solutions
Answer 250235 by Fombitz(13828) on 2010-09-30 09:46:51 (Show Source):
You can put this solution on YOUR website!First,
 does not equal  .
Using the FOIL method,

There is a cross product term.
As an example,

If we did it like you showed,

which is clearly incorrect.
.
.
.
The answer is  but that may not be the complete answer because  is also an answer since
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Geometry_Word_Problems/350112: If the area of a right triangle is 24 square inches and the hypotenuse is 12 inches, find the lengths of the legs of the triagle. 1 solutions
Answer 250233 by Fombitz(13828) on 2010-09-30 09:38:56 (Show Source):
You can put this solution on YOUR website!Let x and y be the legs of the triangle.

1. 
.
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.
2. 
Find the intersection points between these two functions.
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.
.

.
.
.
From eq. 1,

Substitute into eq. 2,

or approximately,
 and 
with corresponding y values of
 and
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Probability-and-statistics/350116: A bag contains 4 blue marbles, 3 red marbles, 2 green marbles and a white marble. You reach in and randomly pick one marble, set it aside, and then randomly pick a second marble. What is the probability of picking two blue marbles? 1 solutions
Answer 250223 by Fombitz(13828) on 2010-09-30 09:10:04 (Show Source):
You can put this solution on YOUR website!4 blue marbles
3 red marbles
2 green marbles
1 white marble
10 total
.
.
.
To choose the 1st blue marble,

To choose the 2nd blue marble,

The probability of choosing both is,
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Graphs/350111: Graph the equation and idenify the y intercept.
y=4x-3
I have unterstood for the most part i just am not understanding how they are getting the points for the variable x 1 solutions
Answer 250221 by Fombitz(13828) on 2010-09-30 09:04:23 (Show Source):
You can put this solution on YOUR website! values are values you choose.
That's the independent variable.
Then once you choose that, the value of  is determined, it's the dependent variable (dependent on your choice of  ).
The y-intercept is the value of  when  .
It's the value of the function when it crosses the y-axis.

(0,-3)
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.
.
Choose any other  value and calculate  .
Then you'll have two points and you can draw your line.
How about  ? Again, doesn't matter, it's your choice.

(2,5)
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.
Now plot the points and connect them with a line.
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.
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Probability-and-statistics/350110: If the probability of a student graduating from college with a 4.0 GPA is 0.008, what is the probability of a student graduating from college with less than a 4.0 GPA? 1 solutions
Answer 250220 by Fombitz(13828) on 2010-09-30 09:00:43 (Show Source):
You can put this solution on YOUR website!Assuming that 4.0 is the highest GPA, then all other scores must be less than 4.0.
P(not 4.0)+P(4.0)=1
P(not 4.0)=1-P(4.0)
P(not 4.0)=1-0.008
P(not 4.0)=0.992
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test/350018: Please help me solve this equation: Sketch the regions enclosed by the given curves and then find the area of the regions.
a. and
b. and
c. and  1 solutions
Answer 250218 by Fombitz(13828) on 2010-09-30 08:58:36 (Show Source):
You can put this solution on YOUR website!
Find the intersection point between  and

So then the area would be,

Expand the terms, integrate, and simplify to get the final answer.
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.
.

Same procedure.
Find the two intersection points  and  by solving,

Proceed as above integrating from one intersection point to the other.

.
.
.

I'm not sure if the first function is  or 
If it's  , then the integration is straightforward since

Integrating that over  to  would give you 
If it's  , then find the intersection point  again where,

Then you have to modify the area because at this point the functions cross.
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test/350079: Please help me solve this equation: Determine the sum for the following series:
(a) 100+10+1+...
(b) 27-9+3-1+... 1 solutions
Answer 250209 by Fombitz(13828) on 2010-09-30 08:28:48 (Show Source):
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Functions/349941: A function is given below. Determine the average rate of change of the function between x = -5 and x = -1.
h(x) = x 2 + 8x 1 solutions
Answer 250158 by Fombitz(13828) on 2010-09-29 23:42:06 (Show Source):
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Probability-and-statistics/349911: A coin is tossed five times. Find the probability that the sixth toss is a tail, given that the first five tosses were all tails.
If a die is rolled one time, find the probability of getting a number greater than five.
If one card is drawn from an ordinary deck of cards, what is the probability that the card will be an ace, a king of hearts, or a spade.
A pet supplier has a stock of parkeets of which thirty percent are blue parakeets. A pet store orders three parakeets from this supplier. If supplier selects the parakeets at random, what is the chance that the pet store gets exactly one blue parakeet?
A university has 10,000 students of which 4000 are male and 6000 are female. If a class of 30 students is chosen at random from university population, find the mean and variance of the number of male students.
1 solutions
Answer 250073 by Fombitz(13828) on 2010-09-29 20:12:13 (Show Source):
You can put this solution on YOUR website!I'll do 4 of the problems.
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a) P(T)=P(H)=1/2, it's independent of previous tosses if the coin is fair.
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b) P(6)=1/6
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c) P(Ace)=4/52=1/13
P(King of Hearts)=1/52
P(Spade)=4/52=1/13
P(Ace or K Hearts or Spade)=P(Ace)+P(K Hearts)+P(Spade)-P(Ace of Spades)
So we don't double count the Ace of Spades as an Ace and a Spade.
P(Ace of Spades)=1/52
P(Ace or K Hearts or Spade)=4/52+1/52+13/52-1/52=17/52
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d) P(B,NB,NB)=0.3(0.7)(0.7)
P(NB,B,NB)=0.7(0.3)(0.7)
P(NB,NB,B)=0.7(0.7)(0.3)
P(1 B)=3(0.3)(0.7)(0.7)=0.441
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Exponents/349867: I figured out the answer but I cannot do the equation. here is the problem.
A 2000L tank containing 550L of water is being filled with water at the rate of 75L per minute from a full 1600L tank. How long will it be before the two tanks have the same amount of water?
Thank you. 1 solutions
Answer 250067 by Fombitz(13828) on 2010-09-29 20:03:36 (Show Source):
You can put this solution on YOUR website!Find the amount of water in tank 1 (2000 L): 
Find the amount of water in tank 2 (1600 L): 
When does  ???
Find  .

Take it from there to solve for  .
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