Which expression is equivalent to 8+18a−2+6a ?

A survey shows that college students spend on average about $20 per month on Yum Good Ramen. a. Assume that the survey was condu

lawyer [7]

Answer:

a) The 95% confidence interval would be given by (19.168;20.832)

b) The 95% confidence interval would be given by (19.182;20.416)

c) The 95% confidence interval would be given by (19.412;20.588)

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

$\mu$ population mean (variable of interest)

$\sigma$ represent the population standard deviation

n represent the sample size

Part a

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

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

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.025,0,1)".And we see that $z_{\alpha/2}=1.96$

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

$20-1.96\frac{6}{\sqrt{200}}=19.168$

$20+1.96\frac{6}{\sqrt{200}}=20.832$

So on this case the 95% confidence interval would be given by (19.168;20.832)

Part b

For this case we just need to change the value for the deviation

$20-1.96\frac{3}{\sqrt{200}}=19.584$

$20+1.96\frac{3}{\sqrt{200}}=20.416$

So on this case the 95% confidence interval would be given by (19.182;20.416)

Part c

For this case we change again the deviation and the sample size.

$20-1.96\frac{6}{\sqrt{400}}=19.412$

$20+1.96\frac{6}{\sqrt{400}}=20.588$

So on this case the 95% confidence interval would be given by (19.412;20.588)

7 0

3 years ago

The standard form of a linear equation is Ax + By = C. Rewrite this equation in slope-slope-intercept form. What is the slope? W

Paraphin [41]

The wander is B=3y the way to figure that out is by adding each of the numbers together

7 0

4 years ago

Please help ASAP!!<br><br> Does the series converge or diverge ?

Snowcat [4.5K]

Answer: It converges

Step-by-step explanation:

To find the sum just use symbolab on google to solve it

3 0

3 years ago

A number has only 1 factor pair. One of its factors is twice the other factor. What is the number? Explain.

Mrrafil [7]

<h3>Answer: 2</h3>

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Explanation:

If a number only has one factor pair, then that number must be prime. This is because prime numbers only have factors of 1 and the number itself.

For instance, the value 7 is prime because the only factors of this are 1 and 7.

For something like the number 32, it is composite and not prime because it has the factors {1,2,4,8,16,32} and it leads to these three factor pairs: 1*32, 2*16, 4*8. This is one example showing why the answer isn't composite.

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Let's say that p is the unknown prime we want to find. The factors of this are 1 and p. We're told that "one of the factors is twice the other factor", so that must mean p = 2*1 = 2. We can see that 2 is twice that of 1.

8 0

3 years ago

Factor this Polynomial completely. X^2-12x-36

Brut [27]

this cannot be factored.

there are no 2 numbers that when added will equal - 12 and when multiplied together would equal -36

6 0

4 years ago