Answer:

Step-by-step explanation:
We are given the following in the question:
Sample size, n = 67
Variance = 3.85
We have to find 80% confidence interval for the population variance of the weights.
Degree of freedom = 67 - 1 = 66
Level of significance = 0.2
Chi square critical value for lower tail =

Chi square critical value for upper tail =

80% confidence interval:

Putting values, we get,

Thus, (3.13,4.91) is the required 80% confidence interval for the population variance of the weights.
Answer:
a is 5 so the perinmeter is 30
Answer:
42.5
Step-by-step explanation:
2x+y=6
y=6-2x and y=x^2-4x+3
The solution occurs when they are equal so we can say y=y which is:
x^2-4x+3=6-2x add 2x to both sides
x^2-2x+3=6 subtract 6 from both sides
x^2-2x-3=0 factor
(x+1)(x-3)=0
So x=-1 and 3, using y=6-2x we find the corresponding y values...
y(-1)=6--2=8, y(3)=6-6=0 so the two solutions are the points:
(-1,8) and (3,0)
Answer:
( since they're similar, they are proportional to each other)
1 (7.2) = h (1.6) (set the two up as a proportion and then cross multiply)
7.2 = 1.6h (divide both sides by 1.6)
h = 4.5 m (this is the answer)
Step-by-step explanation: