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Probability-and-statistics/346137: A game consists of tossing a fair die and then (blindly) selecting a card from a 52 card deck. You win the to prize if the top number on your tossed die is a 1 and you draw a red card. What are the odds against your winning the top prize? 1 solutions
Answer 247561 by Fombitz(13828) on 2010-09-21 14:30:47 (Show Source):
You can put this solution on YOUR website!Let's calculate the odds of actually winning first.
P(1 on die)= 
P(red card)= 
P(1 and red)= 
So then
P(not(1 and red))+P(1 and red)= 
P(not(1 and red))=1-P(1 and red)
P(not(1 and red))= 
P(not(1 and red))= 
So the chances of not winning are 
In terms of odds, there is 1 chance of winning, 11 chances of not winning.
Odds are 11:1 against winning.
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Linear-equations/346208: 2(z + 3)/3 =5 - z answer is 9/5
can anyone give me a full break down on why the answer is 9/5 im getting a totally incorrect answer please help 1 solutions
Answer 247559 by Fombitz(13828) on 2010-09-21 14:26:44 (Show Source):
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Equations/346182: a^3-2a^2-4a-8=0
How would I solve this? 1 solutions
Answer 247558 by Fombitz(13828) on 2010-09-21 14:24:15 (Show Source):
You can put this solution on YOUR website!You can graph it to find out how many roots are real.
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There is one real root.
The other two are complex.
I iterated using Newton's method,

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The approximate complex roots are,
 from www.wolframalpha.com
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Linear-equations/346196: -2/3 x = 5/9 the answer is -5/6
Im having problems solving linear equations with fractions can anyone give me a full break down as per why the answer is -5/6? i know -2/3 has to get multiplied to both sides for the x to be alone but i'm lost after that. 1 solutions
Answer 247552 by Fombitz(13828) on 2010-09-21 13:58:47 (Show Source):
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Angles/346197: In triangle ABC, the measure of angle C is four times the measure of angle A, and the measure of angle B is 18° more than the measure of angle C. Find the measure of each angle of the triangle.
how do i get a formula for this? 1 solutions
Answer 247551 by Fombitz(13828) on 2010-09-21 13:55:32 (Show Source):
You can put this solution on YOUR website!Since it's a triangle, you know that

From the description,

Now you can substitute into the first equation and only have  as a variable.
Solve for  , then go back and solve for  and  .
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Radicals/346195: Please explain the steps on how to find the domain of 27x + 1 over the square root of 3 - x.
Thank you 1 solutions
Answer 247550 by Fombitz(13828) on 2010-09-21 13:53:35 (Show Source):
You can put this solution on YOUR website!The domain is all of the x values where the function is defined.
The square root is defined only when the argument is not negative.
A function is defined when the denominator is not zero.
So the square root argument can't be zero either.
Solve for

That's the only restriction.
The domain of the function is then (  ,  ).
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Exponents/346187: Simplify your answers. Assume no denominators are 0.
Show cancelling and factoring.
1. b(2)/5 divided by b
Please help me!!
1 solutions
Answer 247544 by Fombitz(13828) on 2010-09-21 13:42:09 (Show Source):
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Exponents/346190: Solve for the variable in each equation below. Show all your work. Provide a check for each answer. If a solution is undefined, state that in your answer.
b/2 - b/5 =6
CHECK.
Help me please, I'm stuck! Thank you! 1 solutions
Answer 247543 by Fombitz(13828) on 2010-09-21 13:41:10 (Show Source):
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Vectors/346177: two cars leave a crossroads at the same time. One heads north at 50 km/h and the other heads east at 70 km/h. How far apart are the cars after .5 h? after 2.0 h? 1 solutions
Answer 247540 by Fombitz(13828) on 2010-09-21 13:35:50 (Show Source):
You can put this solution on YOUR website!Rate*Time=Distance
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Since they are traveling in perpendicular directions, you can use the Pythagorean theorem to calculate the distance between them (the hypotenuse).

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Now you have the distance as a function of time.
When  ,  miles
Do the same fo the other times.
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Rational-functions/346178: please factor completely
4c^2+9-12c
What do I do first? 1 solutions
Answer 247532 by Fombitz(13828) on 2010-09-21 13:21:06 (Show Source):
You can put this solution on YOUR website!
Oops!
You're correct that is the answer.
Sorry for screwing you up there.
(2c-3)(2c-3)=4c^2-6c-6c+9=4c^2-12c+9
I will correct it on the website too.
I could say I was just testing you but I just screwed up.
Good work!
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Probability-and-statistics/346172: What is the probability that a number selected at random from the first 500 positive integers is (exactly) divisible by 6 or 9? 1 solutions
Answer 247525 by Fombitz(13828) on 2010-09-21 13:16:07 (Show Source):
You can put this solution on YOUR website!There are  numbers exactly divisible by 6 from 6 to 498.
There are  numbers exactly divisible by 9 from 9 to 495.
There are  numbers that are exactly divisible by 6 and 9 from 18 to 486, we don't want to double count those.
There are 500 numbers total.
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Vectors/346134: Find the cross product of the <2, -1, 4> and <6, -2, 1>. Is the resulting vector perpendicular to given vector? 1 solutions
Answer 247506 by Fombitz(13828) on 2010-09-21 11:27:46 (Show Source):
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test/346095: Graph each equation. Check your work.
-2x+5y=-10 1 solutions
Answer 247504 by Fombitz(13828) on 2010-09-21 11:24:39 (Show Source):
You can put this solution on YOUR website!Find the intercepts.
To find the x-intercept, set  and solve for  .

(  ,  )
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To find the y-intercept, set  and solve for  .

(  ,  )
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Plot the points and connect them with a line.
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