Can someone help me with this? Please-

Use the information provided to determine a 95% confidence interval for the population variance. A researcher was interested in

Leno4ka [110]

Answer:

The 95% confidence interval for the population variance is (8.80, 32.45).

Step-by-step explanation:

The (1 - α)% confidence interval for the population variance is given as follows:

$\frac{(n-1)\cdot s^{2}}{\chi^{2}_{\alpha/2}}\leq \sigma^{2}\leq \frac{(n-1)\cdot s^{2}}{\chi^{2}_{1-\alpha/2}}$

It is provided that:

n = 20

s = 3.9

Confidence level = 95%

⇒ α = 0.05

Compute the critical values of Chi-square:

$\chi^{2}_{\alpha/2, (n-1)}=\chi^{2}_{0.05/2, (20-1)}=\chi^{2}_{0.025,19}=32.852\\\\\chi^{2}_{1-\alpha/2, (n-1)}=\chi^{2}_{1-0.05/2, (20-1)}=\chi^{2}_{0.975,19}=8.907$

*Use a Chi-square table.

Compute the 95% confidence interval for the population variance as follows:

$\frac{(n-1)\cdot s^{2}}{\chi^{2}_{\alpha/2}}\leq \sigma^{2}\leq \frac{(n-1)\cdot s^{2}}{\chi^{2}_{1-\alpha/2}}$

$\frac{(20-1)\cdot (3.9)^{2}}{32.852}\leq \sigma^{2}\leq \frac{(20-1)\cdot (3.9)^{2}}{8.907}\\\\8.7967\leq \sigma^{2}\leq 32.4453\\\\8.80\leq \sigma^{2}\leq 32.45$

Thus, the 95% confidence interval for the population variance is (8.80, 32.45).

4 0

3 years ago

What is the answer and work for these attached below

GrogVix [38]

-4(-5-b)=1/3(b+16) Multiply both sides by 3 to get rid of the fraction
-12(-5-b)=b+16 distribute the -12 to get rid of the parenthesis
60+12b=b+16 get the b on the left side and non b values to the right side
11b=-44 solve for b
b=-44/11 simplify the fraction
b=-4

3/5(t+18)=-3(2-t) multiply both sides by 5/3 to get rid of thefraction
t+18=-5(2-t) distribute the -5 to get rid of the parenthises
t+18=-10+5t get the t to the left side and non t values to the right
-4t=-28 solve for t
t=7

5 0

3 years ago

Is (ab^2) equivalent to ab^2? Explain.

Zarrin [17]

Answer: yes it is equivalent!

Step-by-step explanation:

all you do is take away the parentheses and then it is the same exact thing!

6 0

2 years ago

Read 2 more answers

Which number line represents the solution set for the inequality –4(x + 3) ≤ –2 – 2x?

Delicious77 [7]

Answer:

–4(x + 3) ≤ –2 – 2x

>>.....-4x -12 ≤ -2 -2x

>> -12 +2 ≤ +2x

>> - 10 ≤ 2x

>> -5 ≤ x............>> x >= -5

Step-by-step explanation:

you didn't post any number lines...

3 0

3 years ago

I need help with this math question

ICE Princess25 [194]

Answer:

B. 5

Step-by-step explanation:

Step 1: Rewrite the equation a bit

$\frac{7^\frac{3}{4}}{7^\frac{x}{8}}=\sqrt[8]{7}\\7^\frac{3}{4}^-^\frac{x}{8}=7^\frac{1}{8}$

Step 2: Place a logarithm base 7 on both sides

$7^\frac{3}{4}^-^\frac{x}{8}=7^\frac{1}{8}\\log_77^\frac{3}{4}^-^\frac{x}{8}=log_77^\frac{1}{8}\\(\frac{3}{4}-\frac{x}{8})log_77=\frac{1}{8}log_77\\(\frac{3}{4}-\frac{x}{8})1=\frac{1}{8}1\\\frac{3}{4}-\frac{x}{8}=\frac{1}{8}$

Step 3: Solve for x

$\frac{3}{4}-\frac{x}{8}=\frac{1}{8}\\\frac{6}{8}-\frac{x}{8}=\frac{1}{8}\\-\frac{x}{8}=-\frac{5}{8}\\\frac{x}{8}=\frac{5}{8}\\x=5$

Neat exponent question :)

7 0

2 years ago