A natural gas company charges a $21.08 connection fee plus $2.21 per 8 cubic feet of gas used. In the winter peak usage months,

A student researcher compares the heights of men and women from the student body of a certain college in order to estimate the d

maria [59]

Answer:

(0.6613, 8.3387)

Step-by-step explanation:

Let the heights of men be the first population and the heights of women be the second population. Then

We have $n_{1} = 15$ , $\bar{x}_{1} = 69.4$ , $s_{1} = 3.09$ and

$n_{2} = 7$ , $\bar{x}_{2} = 64.9$ , $s_{2} = 2.58$ . The pooled

estimate is given by

$s_{p}^{2} = \frac{(n_{1}-1)s_{1}^{2}+(n_{2}-1)s_{2}^{2}}{n_{1}+n_{2}-2} = \frac{(15-1)(3.09)^{2}+(7-1)(2.58)^{2}}{15+7-2} = 8.68$

The 99% confidence interval for the true mean difference between the mean height of the men and the mean height of the women is given by (if the samples are independent)

$(\bar{x}_{1}-\bar{x}_{2})\pm t_{0.01/2}s_{p}\sqrt{\frac{1}{15}+\frac{1}{7}}$ , i.e.,

$(69.4-64.9)\pm t_{0.005}2.946\sqrt{\frac{1}{15}+\frac{1}{7}}$

where $t_{0.005}$ is the 0.5th quantile of the t distribution with (15+7-2) = 20 degrees of freedom. So

$4.5\pm(-2.845)(2.946)(0.458)$ , i.e.,

(0.6613, 8.3387)

5 0

3 years ago

Solve: 4x - 8 > 32 A) X <10 B)x > -10 C) X > 10 D) X < -10

larisa [96]

Answer:

C) x > 10

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Equality Properties

Multiplication Property of Equality
Division Property of Equality
Addition Property of Equality
Subtract Property of Equality

Step-by-step explanation:

Step 1: Define

4x - 8 > 32

Step 2: Solve for x

Add 8 on both sides: 4x > 40
Divide 4 on both sides: x > 10

Here we see that any value x greater than 10 would work as a solution to the inequality.

7 0

3 years ago

Find x if x-l/x-1=-1

shusha [124]

X= X^2 hope it helps :)

8 0

4 years ago

Bo and Brica are yoga instructors. Between the both of them, they teach 46 yoga classes each week. If Brica teaches 11 fewer tha

PtichkaEL [24]

Bo teaches 19 classes and Brica teaches 27 classes per week

Step-by-step explanation:

Bo and Brica are yoga instructors

They teach 46 yoga classes each week
Brica teaches 11 fewer than twice as many as Bo

We need to find how many classes each instructor teaches per week

Assume that Bo teaches x classes per week

∵ Bo teaches x classes per week

∵ Brica teaches 11 fewer than twice as many as Bo

∵ Twice means times 2 and 11 fewer is - 11

- Multiply x by 2 and subtract 11 from the product

∴ Brica teaches 2x - 11 classes per week

∵ They teach 46 classes per week

- Add the number of their classes and equate the sum by 46

∴ x + 2x - 11 = 46

- Add the like terms in the left hand side

∴ 3x - 11 = 46

- Add 11 to both sides

∴ 3x = 57

- Divide both sides by 3

∴ x = 19

∵ Bo teaches x classes per week

∴ Bo teaches 19 classes per week

∵ Brica teaches 2x - 11 classes per week

∴ Brica teaches 2(19) - 11 = 27 classes per week

Bo teaches 19 classes and Brica teaches 27 classes per week

Learn more:

You can learn more about the linear equations in brainly.com/question/11306893

#LearnwithBrainly

5 0

3 years ago

Hi right now im doing homework about common denominators and for some reason I cant understand how to do it

goldenfox [79]

It would be great if you added some more details, but for common denominators you try to find the least common number that the 2 or more of the numbers you got have!
For example:
1/2 and 2/3 if you multiply 2 by 3 and 3 by 2, they both are 6, so you would multiply 1/2 both by 3 to make it into 3/6 and 2/3 by 2 to make it into 4/6!

6 0

4 years ago

Read 2 more answers