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This means that you win $12 if you succeed and you lose $1 if you fail. Find the expected value(to you) of the game. Round to the nearest cent. 1 solutions
Answer 232946 by solver91311(16885) on 2010-07-24 20:18:58 (Show Source):
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Probability-and-statistics/325275: When two balanced dice are rolled,there are 36 possible outcomes. Find the probability that the sum is a multiple of 3 or greater than 8. 1 solutions
Answer 232940 by solver91311(16885) on 2010-07-24 19:27:17 (Show Source):
You can put this solution on YOUR website!
Successful outcomes are 3, 6, 9, 10, 11, 12. 2, 4, 5, 7, and 8 don't count because none of them are either multiples of 3 or greater than 8. (8 is just 8, NOT greater than 8).
To make a 3 you need 1 & 2 or 2 & 1, so 2 ways.
To make a 6 you need 1 & 5, 2 & 4, 3 & 3, 4 & 2, or 5 & 1, so 5 ways.
You get to figure out the number of ways to make each of 9, 10, 11, and 12.
Once you have determined the number of ways to make each of the allowable combinations, add them all up to make the numerator of your probability fraction. You already have the denominator, i.e. the number of possible outcomes.
John

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Polynomials-and-rational-expressions/324714: The polynomial 0.041h-0.018a-2.69 can be used to estimate the lung capacity in liters of a female with height h in centimetersand age a in years. Find the lng capacity of a 20 year old woman who is 170 centimenters tall?
I think it is 3.92 liters am I right? 1 solutions
Answer 232473 by solver91311(16885) on 2010-07-22 14:24:08 (Show Source):
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Probability-and-statistics/324753: A home security system is designed to be triggered in 97% of attempted burglaries. If 10 homes equipped with such a system experience an attempted burglary, find the probability that at least 9 alarms are triggered. Round your answer to four decimal places 1 solutions
Answer 232471 by solver91311(16885) on 2010-07-22 14:17:19 (Show Source):
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Quadratic_Equations/324734: Glenn cuts half a rectangular lawn, 40m by 30m, by mowing strips of equal width around the perimeter. Brad cuts the small rectangular left. How wide a strip does Glenn cut so that they share the work equally? I need to solve using the quadratic formula. 1 solutions
Answer 232468 by solver91311(16885) on 2010-07-22 14:04:37 (Show Source):
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Travel_Word_Problems/324748: Can someone please help me work through this word problem?
A flare is fired directly upward into the air from a boat that is experiencing engine problems. The height of the flare (in feet) above the water, t seconds after being fired, is given by the formula h = -16t2 + 128t + 15. If the flare is designed to explode when it reaches its highest point, at what height will this occur?
Thank you,
Alberto
beto@san.rr.com 1 solutions
Answer 232463 by solver91311(16885) on 2010-07-22 13:53:12 (Show Source):
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Functions/324697: I need help with two questions please.
1. Find the inverse of the one-to-one function f)x) = (x - 2)^3.
2. The function f(x) = (x + 1)/(2x - 1) is a one-to-one function. What is the range of f^1(x)? 1 solutions
Answer 232430 by solver91311(16885) on 2010-07-22 11:55:04 (Show Source):
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Matrices-and-determiminant/324567: find the determinant and inverse of the following matrices:
use the Gauss Jordan Method for the inverse.
1 2 3
0 1 4
0 0 8
I got the determinant, it should be 8. i would like to know if im correct.
thank you. 1 solutions
Answer 232309 by solver91311(16885) on 2010-07-21 22:57:56 (Show Source):
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Functions/324531: For the following function, find the value of f(2). The x+2 is absolute value but didn't know how to represent that with keystrokes so I used the backslash key. And I did <- for less than equal to and >- for greater than equal to.
f(x)= {/x+2/ if -4 <- x <1
{ 4 if 1 <- x <3
{-x+5 if x >- 3
1 solutions
Answer 232287 by solver91311(16885) on 2010-07-21 22:20:20 (Show Source):
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logarithm/324536: How do you solve log25(x-1)+log25(x+3)=1/2 1 solutions
Answer 232257 by solver91311(16885) on 2010-07-21 20:25:10 (Show Source):
You can put this solution on YOUR website!
First use: The sum of the logs is the log of the product, that is:
Then use the definition of a logarithm:
Which factors tidily. You will, as is usual with a quadratic equation, get 2 roots. However, in this case, and any time you are solving problems where you start out with functions, such as logarithms, that have restricted domains, you MUST check BOTH answers. It is possible that the original equation will have 2, 1, or 0 valid answers. Remember that the argument of the logarithm function, regardless of the base, must be strictly greater than zero.
John

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test/324529: You drop a penny from a 70-foot high bridge. What is the velocity of the penny when it hits the water below? Neglect the effect of air resistance and round your answer to the nearest unit. 1 solutions
Answer 232255 by solver91311(16885) on 2010-07-21 20:09:05 (Show Source):
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Money_Word_Problems/324444: Suppose I agree to pay you 8 cents for every problem in this class that you solve correctly and fine you 5 cents for every problem done incorrectly. If at the end of 26 problems we do not owe each other any money, how many problems did you solve correctly? 1 solutions
Answer 232210 by solver91311(16885) on 2010-07-21 15:20:41 (Show Source):
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Radicals/324447: Solve for the r in the equation w=Cr^-2. To is the negative power the equation is raised to. then if an object is 100 pnds at sea level. find the value of C that makes the equation true. Sea level is 3,963 miles from the center of the Earth. Use the value of C to answer a place at 282 feet below sea level. and one at 20,320 above sea level. Please show me how to find these answers. 1 solutions
Answer 232208 by solver91311(16885) on 2010-07-21 15:13:38 (Show Source):
You can put this solution on YOUR website!
Part a: "Solve for (something)" means to do whatever is legal to get that something all by itself on one side of the equal sign (typically the left because we read left to right) and everything else on the other side.
Remember that , so the equation becomes:
Multiply both sides by
And divide both sides by w
And finally take the square root of both sides. We only need the positive square root because we are interested in a radius which is a distance.
And that's all there is to that.
Part b: Here you need to solve the equation for C and then plug in the values of 100 for weight and 3963 for r at sea level. We could start over from the original equation, but let's take the easy way and go back to an intermediate result that we obtained doing part a: , which can be written:
Part c:
Here's where you need to be careful with your units. Death Valley is 282 FEET below sea level, but the earth's radius is given in miles. Now we could either convert 282 feet to miles, or 3963 miles to feet. The first way, the numbers are going to be a horror, but the second way, they will be sublimely ridiculous, so let's go with the lesser of two evils.
(approximately, and plenty close enough)
That means that the radius in Death Valley has to be
So, using the original formula:


So if something weighs 100 lbs at sea level, it will gain three thousanths of a pound if you take it to Death Valley.
The Mt. McKinley part is done the same way, just different numbers:
(close enough)
So the radius becomes and

I'll let you do the calculator work from here.
John

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Linear-equations/324446: Can some tell me if I did this right? I suppose to use the elimination method to solve two linear equations. Thanks
7x+3y=15
8x-4y=12
28x+12y=60
24x-12y=48
52x=108
13/27 1 solutions
Answer 232207 by solver91311(16885) on 2010-07-21 15:11:28 (Show Source):
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