Write an equation for a line with a slope of 2, through (4,-2) in standard form.

A classic rock radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you

tia_tia [17]

Answer:

a) $47.917-1.796\frac{2.811}{\sqrt{12}}=46.460$

$47.917+1.796\frac{2.811}{\sqrt{12}}=49.374$

b) Null hypothesis: $\mu =50$

Alternative hypothesis: $\mu \neq 50$

And after analyze the interval obtained the upper limit not contains the value of 50, so then we can conclude that the claim is not satisfied for this case, and the population mean seems to be lower than 50 at 10% of significance.

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

We have the following data: 44 49 45 51 49 53 49 44 47 50 46 48

And we can calculate the sample mean and deviation with the following formulas:

$\bar X= \frac{\sum_{i=1}^n X_i}{n}$

$s= \frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}$

And replacing we got:

$\bar X= 47.917, s= 2.811$

$\mu$ population mean (variable of interest)

n=12 represent the sample size

Part a: Calculate the confidence interval

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

The degrees of freedom are given:

$df= n-1= 12-1=11$

Since the Confidence is 0.90 or 90%, the value of $\alpha=0.1$ and $\alpha/2 =0.05$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.05,11)".And we see that $t_{\alpha/2}=1.796$

Now we have everything in order to replace into formula (1):

$47.917-1.796\frac{2.811}{\sqrt{12}}=46.460$

$47.917+1.796\frac{2.811}{\sqrt{12}}=49.374$

Part b

For this case the system of hypothesis are:

Null hypothesis: $\mu =50$

Alternative hypothesis: $\mu \neq 50$

And after analyze the interval obtained the upper limit not contains the value of 50, so then we can conclude that the claim is not satisfied for this case, and the population mean seems to be lower than 50 at 10% of significance.

6 0

2 years ago

Identify any outlier(s) in the data. {79, 75, 125, 61, 78, 63, 88, 76, 68, 82, 67}

Pepsi [2]

Step-by-step explanation:

In my opinion 125 is an outlier because it is the only 3 digit number

8 0

2 years ago

How do we know how to find an equivalent ratio with 100 as denominator

marta [7]

To find what percent one number is of another number, write the two numbers as a fraction, with the whole as the denominator. Then find an equivalent ratio with a denominator of 100 and write that ratio as a percent.

8 0

2 years ago

Read 2 more answers

What is the distance between the points (21 , 13) and (3 , 13) in the coordinate plane?

Oxana [17]

Answer:

$\displaystyle d = 18$

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Algebra I

Coordinates (x, y)

Algebra II

Distance Formula: $\displaystyle d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

Step-by-step explanation:

Step 1: Define

Identify

Point (21, 13)

Point (3, 13)

Step 2: Find distance d

Simply plug in the 2 coordinates into the distance formula to find distance d

Substitute in points [Distance Formula]: $\displaystyle d = \sqrt{(3-21)^2+(13-13)^2}$
[√Radical] (Parenthesis) Subtract: $\displaystyle d = \sqrt{(-18)^2+(0)^2}$
[√Radical] Evaluate exponents: $\displaystyle d = \sqrt{324+0}$
[√Radical] Add: $\displaystyle d = \sqrt{324}$
[√Radical] Evaluate: $\displaystyle d = 18$

5 0

2 years ago

Please help me!!!!!!! It's very important!!!!

qwelly [4]

You could just use 3.14 or 22/7

6 0

2 years ago