I really need this ASAP

A random sample of 20 items is selected from a population. When computing a confidence interval for the population mean, what nu

kumpel [21]

Answer:

For this case since the sample size is lower than 30 , n =20<30, is not appropiate use the normal standard distribution to calculate the confidence interval for the mean, and then for this case is better use the t distribution since takes in count the correction factor to approximate the distribution of the true parameter.

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

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

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".

$\bar X$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s represent the sample standard deviation

n represent the sample size

Solution to the problem

For this case since the sample size is lower than 30 , n =20<30, is not appropiate use the normal standard distribution to calculate the confidence interval for the mean, and then for this case is better use the t distribution since takes in count the correction factor to approximate the distribution of the true parameter.

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

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

8 0

3 years ago

What is the y-intercept of f(x)=3/5x<br> a. (1, 0)<br> b. (1, 3/5)<br> c. (0, 0)<br> d. (0, 1)

Digiron [165]

Answer
F(0)=0

I can put the work in the comments if you need it :)

4 0

2 years ago

Lea buys 20 picture frames. Some are 4 in. by 6 in. frames which cost $5.80 each, and the rest are 5 in. by 7 in. frames that co

MAXImum [283]

To find the answer we have to slowly analyze the command.
For surely on the one side we want to have total cash spent, so 80.8$
We know that there are 2 types of frames 5,80$ and 9.60$.
We know too, that f is the number of frames 5.80$ bought.
Simply, to find the cash spent on those frames we have to just mulitply 5.80$ times f, so we obtain $f*5.8$ .
We can say that number of bigger frames is 20-f.
So to find cash spent on bigger frames we have to multiply 9.60$ times (20-f), so
$9.60*(20-f)$
Now we can just add cost of all frames together
$f*5.80+9.60(20-f)$
And we know that is equal to 80.8, so
$f*5.80+9.60(20-f)$ =80.8

As we can see, the answer is b.

5 0

2 years ago

The legs of a right triangle measure 10 m and 24 m. What is the length of

SVETLANKA909090 [29]

Answer:

26

Step-by-step explanation:

100 +(24^2) = 676

square root of 676 = 26

3 0

3 years ago

Read 2 more answers

(1 point) A particle starts at the point P=(−2,−1,3)P=(−2,−1,3) when t=0t=0 and moves along a straight line toward Q=(−4,0,6)Q=(

Ahat [919]

Answer:

The position is given by r(t) = (-2 -t √14, 1 + √3.5, 3 + 3√3.5)

Step-by-step explanation:

The direction is given by the difference between the starting point and the end point, thus it is (-4,0,6)-(-2,-1,3) = (-2,1,3). The norm of this vector is √( (-2)²+1²+3²) = √14 = 3.7416 secons

Since the speed is 7 cm/sec, we need to multiply this vector by 7/√14 = √3.5 in order to obtain how much does the particle advance each second.

As a consecuence, it advances (-2,1,3) * √3.5 = (- √14, √3.5, 3 √3.5)

And, as a result, the position after t seconds is given by the function

r(t) = (-2,1,3) + t (-√14, √3.5, 3 √3.5) = (-2 -t √14, 1 + √3.5, 3 + 3√3.5)

8 0

3 years ago