What's 12+89+75+54+43+23=? <br> LOL!!!

Kazeer [188]

Multiply 4.93m by 8.5m to get 41.905m to the second power.

You do this because there are 2 identical triangles on the top. And if you put those two triangles together, you get a rectangle. The length of the rectangle is 8.5m while the width would be 4.93. Multiplying the length and width gives you the area.

Then multiply 10.2m by 8.5m to get 86.7m to the second power.

You do this because there are 2 identical triangles on the bottom. And if you put those two triangles together, you get another rectangle. The length of the rectangle is 8.5m while the width would be 10.2m. Multiplying those together gives you the area.

You then add the two areas, 41.905m to the second power and 86.7m to the second power, to get the area of the entire figure.

After adding, you get 128.605 m to the second power. That's the answer

5 0

3 years ago

An SRS of 350 high school seniors gained an average of x¯=21 points in their second attempt at the SAT Mathematics exam. Assume

Lynna [10]

Answer:

a) $21-2.58\frac{52}{\sqrt{350}}=13.83$

$21+2.58\frac{52}{\sqrt{350}}=28.17$

So on this case the 99% confidence interval would be given by (13.83;28.17)

b) $ME=2.58\frac{52}{\sqrt{350}}=7.17$

c) $ME=2.58\frac{52}{\sqrt{100}}=13.42$

d) D. Decreasing the sample size increases the margin of error, provided the confidence level and population standard deviation remain the same.

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".

Part a

$\bar X=21$ represent the sample mean

$\mu$ population mean (variable of interest)

$\sigma=52$ represent the population standard deviation

n=350 represent the sample size

99% confidence interval

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 0.99 or 99%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.005,0,1)".And we see that $z_{\alpha/2}=2.58$

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

$21-2.58\frac{52}{\sqrt{350}}=13.83$

$21+2.58\frac{52}{\sqrt{350}}=28.17$

So on this case the 99% confidence interval would be given by (13.83;28.17)

Part b

The margin of error is given by:

$ME=2.58\frac{52}{\sqrt{350}}=7.17$

Part c

The margin of error is given by:

$ME=2.58\frac{52}{\sqrt{100}}=13.42$

Part d

As we can see when we reduce the sample size we increase the margin of error so the best option for this case is:

D. Decreasing the sample size increases the margin of error, provided the confidence level and population standard deviation remain the same.

6 0

2 years ago

A gumball machine has 78 gumballs. each person who puts a coin into the machine gets 3 gumballs. after a certain number of peopl

Lesechka [4]

D is the bast answer for this question, but, the equation should be (78-54)/3=p.

8 0

3 years ago

Read 2 more answers

Given ∆ABC, with a = 9 , b = 8 and c =13, find angle c

strojnjashka [21]

Answer:

angle c is 13 as it said in the question

Step-by-step explanation:

6 0

2 years ago

#7 please help!!!!!!!!!!!!!!!!!!!!!!!!!

Ira Lisetskai [31]

If they all painted at the same rate the equation is this

mothers 8
daughters 12 at 220 sq ft

mothers 6
daughters 8 at 152 sq ft

220 +152 =372 divided by 34 (because they all painted at the same rate)=10.94 sq ft they each painted

4 0

3 years ago

What's 12+89+75+54+43+23=? LOL!!!