Answer:
The confidence interval for the population variance of the thicknesses of all aluminum sheets in this factory is Lower limit = 2.30, Upper limit = 4.83.
Step-by-step explanation:
The confidence interval for population variance is given as below:
![[(n - 1)\times S^{2} / X^{2} \alpha/2, n-1 ] < \alpha < [(n- 1)\times S^{2} / X^{2} 1- \alpha/2, n- 1 ]](https://tex.z-dn.net/?f=%5B%28n%20-%201%29%5Ctimes%20S%5E%7B2%7D%20%20%2F%20%20X%5E%7B2%7D%20%20%5Calpha%2F2%2C%20n-1%20%5D%20%3C%20%5Calpha%20%3C%20%5B%28n-%201%29%5Ctimes%20S%5E%7B2%7D%20%20%2F%20X%5E%7B2%7D%201-%20%5Calpha%2F2%2C%20n-%201%20%5D)
We are given
Confidence level = 98%
Sample size = n = 81
Degrees of freedom = n – 1 = 80
Sample Variance = S^2 = 3.23
![X^{2}_{[\alpha/2, n - 1]} = 112.3288\\\X^{2} _{1 -\alpha/2,n- 1} = 53.5401](https://tex.z-dn.net/?f=X%5E%7B2%7D_%7B%5B%5Calpha%2F2%2C%20n%20-%201%5D%7D%20%20%20%3D%20112.3288%5C%5C%5CX%5E%7B2%7D%20_%7B1%20-%5Calpha%2F2%2Cn-%201%7D%20%3D%2053.5401)
(By using chi-square table)
[(n – 1)*S^2 / X^2 α/2, n– 1 ] < σ^2 < [(n – 1)*S^2 / X^2 1 -α/2, n– 1 ]
[(81 – 1)* 3.23 / 112.3288] < σ^2 < [(81 – 1)* 3.23/ 53.5401]
2.3004 < σ^2 < 4.8263
Lower limit = 2.30
Upper limit = 4.83.
Answer: False
Step-by-step explanation: Skinfold measurements is one of the oldest ways of measuring a person's fat percentage,it's usually taken in specific areas of the body where there are Skinfolds,while taking this measurements it is expected that the person taking it does the average of 2or more repeated measurements in order to ensure that the actual thickness of that area of the body is correctly entered.
It is specifically taken from the right side of the body,where the person pinches out the Skinfolds away from the body by attaching a caliper ,this is to ensure that only the fatty laters are considered, it is mainly presented in percentage.
Answer:
Step-by-step explanation:
n+21
The slope intercept form is y = -x - 4
To find the slope intercept form given a couple of points, start by finding the slope using the slope equation.
m(slope) = (y2 - y1)/(x2 - x1)
m = (-5 - 0)/(1 - -4)
m = -5/5
m = -1
Now we look for the intercept using slope intercept form, our slope and a point.
y = mx + b
0 = -4(-1) + b
0 = 4 + b
-4 = b
Now we can use those two things top model the equation.
y = -x - 4