Ask question

Ask question

All categories

3 years ago

12

Prevent as a decimal 21%

1 answer:

zalisa [80]3 years ago

7 0

Answer:

0.21

Step-by-step explanation:

21 / 100 =0.21

You might be interested in

Evaluate the function for x = –2a, if a = 3.

Snezhnost [94]

The answer that you should get is A

8 0

3 years ago

Suppose that the researchers wanted to estimate the mean reaction time to within 6 msec with 95% confidence. Using the sample st

Lisa [10]

Answer:

a) The 95% confidence interval would be given by (509.592;550.308)

b) n=523 rounded up to the nearest integer

Step-by-step explanation:

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".

$\bar X=530$ represent the sample mean for the sample

$\mu$ population mean

s=70 represent the sample standard deviation

n=48 represent the sample size (variable of interest)

Confidence =95% or 0.995

Part a

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

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

The degrees of freedom are df=n-1=48-1=47

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: "=-T.INV(0.025,47)".And we see that $z_{\alpha/2}=2.01$

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

$530-2.01\frac{70}{\sqrt{48}}=509.692$

$530+2.01\frac{70}{\sqrt{48}}=550.308$

So on this case the 95% confidence interval would be given by (509.592;550.308)

Part b

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (a)

Assuming that $\hat \sigma =s$

And on this case we have that ME =6msec, and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=(\frac{z_{\alpha/2} \sigma}{ME})^2$ (b)

The critical value for 95% of confidence interval is provided, $z_{\alpha/2}=1.96$ , replacing into formula (b) we got:

$n=(\frac{1.96(70)}{6})^2 =522.88 \approx 523$

So the answer for this case would be n=523 rounded up to the nearest integer

3 0

3 years ago

6 3/4x5=?<br><br> Please help

lesantik [10]

The answer would be 33 3/4.

8 0

3 years ago

If you are smart then you know the answer : what is 3 x 4 - 5 - 6 + 99 - 5 x 5 x 100 x 50 x 575 x 2 - 100 + 399

PilotLPTM [1.2K]

Answer: -143749601 :)

Step-by-step explanation:

4 0

2 years ago

Read 2 more answers

Find the slope and y-intercept for the two linear functions. Linear Functions Identify the slope of the line given in the table:

Natalija [7]

ANSWER

See explanation

EXPLANATION

The table contains these two points (-4,-3) and (2,-4.5)

The slope of this line is given by;

$m = \frac{rise}{run}$

$m = \frac{ - 4.5 - - 3}{2 - - 4} = \frac{ - 1.5}{6}$

$m = - \frac{1}{4}$

The y-intercept can be obtained by finding the equation of the line in the form:

$y = mx + c$

We plug in the slope and the point (-4,-3) to find c.

This implies that,

$- 3 = - \frac{1}{4} \times - 4 + c$

$- 3 = 1 + c$

$c = - 3 - 1 = - 4$

Hence the y-intercept is -4.

The given line is

$y = \frac{3}{2} x + 1$

This is already in the slope intercept form:

The slope is

$m = \frac{3}{2}$

The y-intercept is c=1

5 0

3 years ago

Read 2 more answers