Please Help!! My area can be represented by the expression x^2. What special polygon am I?

A random sample of 30 households was selected as part of a study on electricity usage, and the number of kilowatt-hours (kWh) wa

grin007 [14]

Answer:

The 98% confidence interval for the mean usage in the March quarter of 2006, in kWh, was (333.87, 416.13).

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 30 - 1 = 29

98% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 29 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.98}{2} = 0.99$ . So we have T = 2.462

The margin of error is:

$M = T\frac{s}{\sqrt{n}} = 2.462\frac{91.5}{\sqrt{30}} = 41.13$

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 375 - 41.13 = 333.87 kWh

The upper end of the interval is the sample mean added to M. So it is 375 + 41.13 = 416.13 kWh

The 98% confidence interval for the mean usage in the March quarter of 2006, in kWh, was (333.87, 416.13).

6 0

3 years ago

How do you get 987589 rounded to the nearest whole number im giving 45 points

lubasha [3.4K]

Answer:

it is a whole number there's something wrong in the question

Step-by-step explanation:

3 0

2 years ago

Read 2 more answers

DISNEY SONG QUIZ FIRST ONE TO GET IT RIGHT GETS BRAINLIEST!!

AysviL [449]

Answer:

D singing

Step-by-step explanation:

Hopefully this is right!

7 0

3 years ago

Help me with this Please.

sukhopar [10]

35
the ratio for the two is 5:7 and you want to find _:49. to get from 7 to 49 you multiply the 7 by 7. because you did that to one side you have to do the same to the other and multiply 5 by 7 which gives you 35

6 0

2 years ago

To test the belief that sons are taller than their fathers, a student randomly selects 13 fathers who have adult male children.

KATRIN_1 [288]

Answer:

1) B. The differences are normally distributed or the sample size is large

C. The sample size mus be large

E. The sampling method results in an independent sample

2) The null hypothesis H₀: $\bar x_1$ = $\bar x_2$

The alternative hypothesis Hₐ: $\bar x_1$ < $\bar x_2$

Test statistic, t = -0.00693

p- value = 0.498

Do not reject Upper H₀ because, the P-value is greater than the level of significance. There is sufficient evidence to conclude that sons are the same height as their fathers at 0.10 level of significance

Step-by-step explanation:

1) B. The differences are normally distributed or the sample size is large

C. The sample size mus be large

E. The sampling method results in an independent sample

2) The null hypothesis H₀: $\bar x_1$ = $\bar x_2$

The alternative hypothesis Hₐ: $\bar x_1$ < $\bar x_2$

The test statistic for t test is;

$t=\dfrac{(\bar{x}_1-\bar{x}_2)}{\sqrt{\dfrac{s_{1}^{2} }{n_{1}}-\dfrac{s _{2}^{2}}{n_{2}}}}$

The mean

Height of Father, h₁, Height of Son h₂

72.4, 77.5

70.6, 74.1

73.1, 75.6

69.9, 71.7

69.4, 70.5

69.4, 69.9

68.1, 68.2

68.9, 68.2

70.5, 69.3

69.4, 67.7

69.5, 67

67.2, 63.7

70.4, 65.5

$\bar x_1$ = 69.6

s₁ = 1.58

$\bar x_2$ = 69.9

s₂ = 3.97

n₁ = 13

n₂ = 13

$t=\dfrac{(69.908-69.915)}{\sqrt{\dfrac{3.97^{2}}{13}-\dfrac{1.58^{2} }{13}}}$

(We reversed the values in the square root of the denominator therefore, the sign reversal)

t = -0.00693

p- value = 0.498 by graphing calculator function

P-value > α Therefore, we do not reject the null hypothesis

Do not reject Upper H₀ because, the P-value is greater than the level of significance. There is sufficient evidence to conclude that sons are the same height as their fathers at 0.10 lvel of significance

8 0

4 years ago