It's the bottom one. Miko found the incorrect and checked her work using multipication incorrectly.
This is because the correct way to solve this would to use (5/1) * (3/5) = (15/5) then simplify it to 3/1 or simply 3.
Dividing fractions is simply flipping the second fraction and then multiplying across
Answer: The mean of the data is 433.75, variance of the data is 99667.19 and the standard deviation of the data is 315.7011.
Explanation:
The given data is 900, 35, 500 and 300.
The number of observation is 4.
Formula of mean is,
![\text{Mean}=\frac{\text{Sum of observations}}{\text{Number of observations}}](https://tex.z-dn.net/?f=%5Ctext%7BMean%7D%3D%5Cfrac%7B%5Ctext%7BSum%20of%20observations%7D%7D%7B%5Ctext%7BNumber%20of%20observations%7D%7D)
![\bar{X}=\frac{900+35+50+300}{4} =433.75](https://tex.z-dn.net/?f=%5Cbar%7BX%7D%3D%5Cfrac%7B900%2B35%2B50%2B300%7D%7B4%7D%20%3D433.75)
The formula of variance is given below,
![\sigma^2=\frac{1}{n}\sum{(X-\bar{X})^2}](https://tex.z-dn.net/?f=%5Csigma%5E2%3D%5Cfrac%7B1%7D%7Bn%7D%5Csum%7B%28X-%5Cbar%7BX%7D%29%5E2%7D)
![\sigma^2=\frac{398668.75}{4}](https://tex.z-dn.net/?f=%5Csigma%5E2%3D%5Cfrac%7B398668.75%7D%7B4%7D)
![\sigma^2=99667.19](https://tex.z-dn.net/?f=%5Csigma%5E2%3D99667.19)
The variance of the data is 99667.19
![\sigma=\sqrt{99667.19}](https://tex.z-dn.net/?f=%5Csigma%3D%5Csqrt%7B99667.19%7D)
![\sigma=315.7011](https://tex.z-dn.net/?f=%5Csigma%3D315.7011)
The standard deviation of the data is 315.7011.
The other information or values of given chart is shown in the attached table.
Answer:
250 - 20 < 80 + 15x
Step-by-step explanation:
Given that
Beth has 250 books and 20 books sold each week
While on the other hand, Martin has 80 books and sell 15 books each week
Let us assume each week be x
Now the equations are
Beth 250 - 20x
Martin 80 + 15 x
Now the inequality would be
250 - 20 < 80 + 15x
T = 5, so after 5 years
p(t) = t^3 - 14t^2 + 20t + 120
Take derivative to find minimum:
p’(t) = 3t^2 - 28t + 10
Factor to solve for t:
p’(t) = (3t - 2)(t - 5)
0 = (3t - 2)(t - 5)
0 = 3t - 2
2 = 3t
2/3 = t
Plug 2/3 into original equation, this is a maximum. We want the minimum:
0 = t - 5
5 = t
Plug back into original:
5^3 - 14(5)^2 + 20(5) + 120
125 - 14(25) + 100 + 120
125 - 350 + 220
- 225 + 220
p(5) = -5