Simplify the expression show work<br><br> -40/-5

Let n1equals50, Upper X 1equals30, n2equals50, and Upper X 2equals10. Complete parts (a) and (b) below. a. At the 0.05 leve

Viefleur [7K]

Answer:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

$z=\frac{0.6-0.2}{\sqrt{0.4(1-0.4)(\frac{1}{50}+\frac{1}{50})}}=4.082$

$p_v =2*P(Z>4.082)=4.46x10^{-5}$

So the p value is a very low value and using any significance level for example $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion 1 is significantly different from proportion 2.

Step-by-step explanation:

1) Data given and notation

$X_{1}=30$ represent the number of people with a characteristic in 1

$X_{2}=10$ represent the number of people with a characteristic in 2

$n_{1}=50$ sample of 1 selected

$n_{2}=50$ sample of 2 selected

$p_{1}=\frac{30}{50}=0.6$ represent the proportion of people with a characteristic in 1

$p_{2}=\frac{10}{50}=0.2$ represent the proportion of people with a characteristic in 2

z would represent the statistic (variable of interest)

$p_v$ represent the value for the test (variable of interest)

2) Concepts and formulas to use

We need to conduct a hypothesis in order to check if the proportion 1 is different from proportion 2 , the system of hypothesis would be:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{30+10}{50+50}=0.4$

3) Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.6-0.2}{\sqrt{0.4(1-0.4)(\frac{1}{50}+\frac{1}{50})}}=4.082$

4) Statistical decision

For this case we don't have a significance level provided $\alpha$ , but we can calculate the p value for this test.

Since is a two sided test the p value would be:

$p_v =2*P(Z>4.082)=4.46x10^{-5}$

So the p value is a very low value and using any significance level for example $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion 1 is significantly different from proportion 2.

3 0

3 years ago

Identify the angles of rotational symmetry for the figure.

miss Akunina [59]

I saw 180, 90, 45. That’s only because 360/8=45 so it’s symmetrical when rotated by a multiple of 45. Hope that helps

3 0

3 years ago

Felipe picked a pumpkin that weighed three times the weight of Meg's pumpkin Meg's pumpkin with half the weight of Ryan's pump R

Xelga [282]

Answer:

21 lb

Step-by-step explanation:

Divide the amount of Ryan's pumpkin by 2 then multiply it by 3. Ryan's pumpkin weighs 14 lb divided by 2 is 7 then 7 multiplied by 3 is 21.

6 0

3 years ago

Lily wants to buy a smartphone, she has $500 to spend .list three ways she can get a good deal

BaLLatris [955]

1. Check the prices of phones from different stores.

2. Do some research to see what is the average cost of the phone.

3. Check for possible discounts.

Hope this helps :)

3 0

3 years ago

Please help quick i get brainliest

IrinaK [193]

Question 1:
If you know that 3 squares equals 7 circles and the squares are being counted by 3, then continue to count the circle by 3 until you get 25 circles.
Example:
3 Squares : 7 circles
4 squares : 10 circles
5 squares : 13 circles
6 squares : 16 circles
7 squares : 19 circles
8 squares : 22 circles
9 squares : 25 circles Add 9 squares to 3 = 12
You will have 12 squares when continues to count all the way to 25 circles.

Question 2:
Just multiply 14 by 28 and you will get your answer. Which is 3. The missing digit's 3. You can then check by doing 392 ÷ 14 to see if you get 28.

6 0

3 years ago

Simplify the expression show work -40/-5