PLEASE HELP-

Marrrta [24]

The answer would be 16

11 + (8-3)^2 - 20 = 16

3 0

2 years ago

The U.S. Census Bureau conducts a study to determine the time needed to complete the short form. The Bureau surveys 200 people.

NISA [10]

Answer:

$8.2-2.58\frac{2.2}{\sqrt{18}}=6.86$

$8.2+2.58\frac{2.2}{\sqrt{18}}=9.54$

So on this case the 90% confidence interval would be given by (6.86;9.54) And the error is given by:

$ME= 2.58\frac{2.2}{\sqrt{18}} =1.338$

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".

$\bar X=8.2$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=2.2$ represent the population standard deviation

n represent the sample size

Solution to the problem

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 0.90 or 90%, the value of $\alpha=0.1$ 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):

$8.2-2.58\frac{2.2}{\sqrt{18}}=6.86$

$8.2+2.58\frac{2.2}{\sqrt{18}}=9.54$

So on this case the 90% confidence interval would be given by (6.86;9.54) And the error is given by:

$ME= 2.58\frac{2.2}{\sqrt{18}} =1.338$

8 0

2 years ago

Read 2 more answers

Ricardo spends 8/9 hour reading the newspaper.he spends 1/4 of the time reading the world news and splits the remaining time equ

guajiro [1.7K]

If he spends 1/4 reading the news, then he spends 3/4 reading the other stuff

3/4 * 8/9 = 24/36 = 2/3 of an hr ...time spent reading sports and comics

(2/3) / 2 =
2/3 * 1/2 = 2/6 reduces to 1/3....so he spends 1/3 of an hour (or 20 minutes) reading the comics

3 0

2 years ago

NEED HELP ON THIS QUESTION ASAP

Katarina [22]

Answer:

Step-by-step explanation:

A+B+C+D=360

A=180 as it half of the circle

B+C+D=180

60+C+90=180

150+C=180

C=180-150=30

The fraction of the circle to region C

30/180=1/6

8 0

3 years ago

Read 2 more answers

Is the following function even,odd, or neither?

Crazy boy [7]

Answer:

1. Even

Step-by-step explanation:

A function is even when it is symmetric over the y-axis. In this case, we have a parabola that has its vertex at (0,10), this means that it is indeed symmetric over they y-axis, so it is even.

7 0

2 years ago