Answer:
81 samples
Step-by-step explanation:
According to the empirical rule :
Possible values of the sample mean is within 3 standard deviations of the population mean :
μ ± 3 sd(x) ; sd(x) = standard deviation of sampling distribution.
3 * sd(x) = 1
sd(x) = 1/3
Recall:
Standard deviation of sampling distribution, sd(x)
sd(x) = σ / sqrt(n)
1/3 = 3 / sqrt(n)
Square both sides
1/9 = 9/n
Cross multiply :
n * 1 = 9 * 9
n = 81
Answer:
Both get the same results that is,
![\left[\begin{array}{ccc}140\\160\\200\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D140%5C%5C160%5C%5C200%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
Given :
![\bf M=\left[\begin{array}{ccc}\frac{1}{5}&\frac{1}{5}&\frac{2}{5}\\\frac{2}{5}&\frac{2}{5}&\frac{1}{5}\\\frac{2}{5}&\frac{2}{5}&\frac{2}{5}\end{array}\right]](https://tex.z-dn.net/?f=%5Cbf%20M%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Cfrac%7B1%7D%7B5%7D%26%5Cfrac%7B1%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%5C%5C%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B1%7D%7B5%7D%5C%5C%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%5Cend%7Barray%7D%5Cright%5D)
and initial population,
![\bf P=\left[\begin{array}{ccc}130\\300\\70\end{array}\right]](https://tex.z-dn.net/?f=%5Cbf%20P%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D130%5C%5C300%5C%5C70%5Cend%7Barray%7D%5Cright%5D)
a) - After two times, we will find in each position.
![P_2=[P].[M]^2=[P].[M].[M]](https://tex.z-dn.net/?f=P_2%3D%5BP%5D.%5BM%5D%5E2%3D%5BP%5D.%5BM%5D.%5BM%5D)
![M^2=\left[\begin{array}{ccc}\frac{1}{5}&\frac{1}{5}&\frac{2}{5}\\\frac{2}{5}&\frac{2}{5}&\frac{1}{5}\\\frac{2}{5}&\frac{2}{5}&\frac{2}{5}\end{array}\right]\times \left[\begin{array}{ccc}\frac{1}{5}&\frac{1}{5}&\frac{2}{5}\\\frac{2}{5}&\frac{2}{5}&\frac{1}{5}\\\frac{2}{5}&\frac{2}{5}&\frac{2}{5}\end{array}\right]](https://tex.z-dn.net/?f=M%5E2%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Cfrac%7B1%7D%7B5%7D%26%5Cfrac%7B1%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%5C%5C%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B1%7D%7B5%7D%5C%5C%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%5Cend%7Barray%7D%5Cright%5D%5Ctimes%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Cfrac%7B1%7D%7B5%7D%26%5Cfrac%7B1%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%5C%5C%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B1%7D%7B5%7D%5C%5C%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%26%5Cfrac%7B2%7D%7B5%7D%5Cend%7Barray%7D%5Cright%5D)
![=\frac{1}{25} \left[\begin{array}{ccc}7&7&7\\8&8&8\\10&10&10\end{array}\right]](https://tex.z-dn.net/?f=%3D%5Cfrac%7B1%7D%7B25%7D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D7%267%267%5C%5C8%268%268%5C%5C10%2610%2610%5Cend%7Barray%7D%5Cright%5D)
![\therefore\;\;\;\;\;\;\;\;\;\;\;P_2=\left[\begin{array}{ccc}7&7&7\\8&8&8\\10&10&10\end{array}\right] \times\left[\begin{array}{ccc}130\\300\\70\end{array}\right] = \left[\begin{array}{ccc}140\\160\\200\end{array}\right]](https://tex.z-dn.net/?f=%5Ctherefore%5C%3B%5C%3B%5C%3B%5C%3B%5C%3B%5C%3B%5C%3B%5C%3B%5C%3B%5C%3B%5C%3BP_2%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D7%267%267%5C%5C8%268%268%5C%5C10%2610%2610%5Cend%7Barray%7D%5Cright%5D%20%5Ctimes%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D130%5C%5C300%5C%5C70%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D140%5C%5C160%5C%5C200%5Cend%7Barray%7D%5Cright%5D)
b) - With in migration process, 500 people are numbered. There will be after a long time,
![After\;inifinite\;period=[M]^n.[P]](https://tex.z-dn.net/?f=After%5C%3Binifinite%5C%3Bperiod%3D%5BM%5D%5En.%5BP%5D)
![Then,\;we\;get\;the\;same\;result\;if\;we\;measure [M]^n=\frac{1}{25} \left[\begin{array}{ccc}7&7&7\\8&8&8\\10&10&10\end{array}\right]](https://tex.z-dn.net/?f=Then%2C%5C%3Bwe%5C%3Bget%5C%3Bthe%5C%3Bsame%5C%3Bresult%5C%3Bif%5C%3Bwe%5C%3Bmeasure%20%5BM%5D%5En%3D%5Cfrac%7B1%7D%7B25%7D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D7%267%267%5C%5C8%268%268%5C%5C10%2610%2610%5Cend%7Barray%7D%5Cright%5D)
![=\left[\begin{array}{ccc}140\\160\\200\end{array}\right]](https://tex.z-dn.net/?f=%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D140%5C%5C160%5C%5C200%5Cend%7Barray%7D%5Cright%5D)
She walks 6/5 of a mile in 1 hour
So, she walks 1.2 miles per hour
The answer would be 6fg^3+5f^2g^2+f^3g-7
She has $12,488 in savings
Step-by-step explanation:
Ariana plans to use $260 less than three-fourths of savings to buy a car.
If the purchase price of the car is 9,340, we need to find how much
she has in savings
To find the savings
- Assume that she has $x in savings
- Write an equation of x
- Solve the equation to find x
∵ She has $x in savings
∵ She plans to use $260 less than three-fourths of savings
- Three-fourths means
and less than means subtract
∴ She plans to use
x - 26
∵ The purchase price of the car is 9,340
- Equate the expression of x by 9,340
∴
x - 26 = 9,340
Now let us solve the equation
∵
x - 26 = 9,340
- Add 26 to both sides
∴
x = 9,366
- Divide both sides by
∴ x = $12,488
She has $12,488 in savings
Learn more:
You can learn more about word problems in brainly.com/question/3950386
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