Can u help me if u understand this

The following prices, in dollars, of 7.5-cubic-foot refrigerators were recorded from a random sample. 314 305 344 283 285 310 3

Mariana [72]

Answer:

$t=\frac{310.9-300}{\frac{31.09}{\sqrt{10}}}=1.109$

The degrees of freedom are given by:

$df=n-1=10-1=9$

And the p value would be given by:

$p_v =P(t_{9}>1.109)=0.148$

Since the p value is higher than the significance level of 0.05 we don't have enough evidence to conclude that the true mean is significantly higher than $300 because we FAIL to reject the null hypothesis.

Step-by-step explanation:

Information given

314 305 344 283 285 310 383 285 300 300

We can calculate the sample mean and deviation with the following formula:

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

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

$\bar X=310.9$ represent the sample mean

$s=31.09$ represent the standard deviation for the sample

$n=10$ sample size

$\mu_o =300$ represent the value to test

$\alpha=0.05$ represent the significance level

t would represent the statistic

$p_v$ represent the p value

Hypothesis to test

We want to verify if the true mean is greater than 300, the system of hypothesis would be:

Null hypothesis: $\mu \leq 300$

Alternative hypothesis: $\mu > 300$

The statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

Replacing the info given we got:

$t=\frac{310.9-300}{\frac{31.09}{\sqrt{10}}}=1.109$

The degrees of freedom are given by:

$df=n-1=10-1=9$

And the p value would be given by:

$p_v =P(t_{9}>1.109)=0.148$

Since the p value is higher than the significance level of 0.05 we don't have enough evidence to conclude that the true mean is significantly higher than $300 because we FAIL to reject the null hypothesis.

6 0

3 years ago

What's bigger 2/3 or 4/5

Eduardwww [97]

The best thing to do is either to find a common denominator or convert them to decimals.
I will find a common denominator.
A common denominator of 3 and 5 is 15.
You multiply the first fraction by 5
2*5= 10
This then becomes 10/15
You then multiply the second by 3.
4*3= 12
Therefore, this becomes 12/15
As the second of these fractions is larger, this means that 4/5 is larger.
The alternative method is to put them into decimals, in which case 2/3= 0.66 and 4/5= 0.8
Hope this helps :)

4 0

3 years ago

Read 2 more answers

How do I do this? Please provide steps.

matrenka [14]

Answer:

3/5

Step-by-step explanation:

Soh Cah Toa

In some trigonometry classes, this acronym is very important to solving questions like this.

Why?

It tells us the right triangle-definition of these trigonometry functions.

We have that cosine of an angle is equal to tge side that is adjacent to it over the hypotenuse.

So here we are asked to find cos(B).

Lets look at triangle respect to the angle B

The measurement of the side that is opposite is 64.

The measurement of the side that is adjacent is 48.

The measurement of the hypotenuse is 80.

So cos(B)=48/80.

Let's reduce. 48 and 80 have a common factor of 8 so divide numerator and dexter by 8. This gives us:

cos(B)=6/10.

One more step in reducing. Both factors are even so cos(B)=3/5.

6 0

3 years ago

What represent the reflection of....

fomenos

The first table is the answer

7 0

3 years ago

The number of painters, p, employed to paint a building is inversely proportional to the time taken to paint the building, b. Wh

koban [17]

The Answer is
c) p=k/b

6 0

3 years ago

Read 2 more answers