The graph shows the function f(x)=2^x what is the value of x when f(x)=4

Lauren would like to have an average of 88 in her math class. There are five assignments with the following grades: 85, 100, 88,

daser333 [38]

80
85+100+88+90+95+80=528
528/6=80

7 0

3 years ago

Included angle between and : ∠A ∠S ∠W

SOVA2 [1]

Angle between SW and WA is <W

hope it helps

9 0

3 years ago

Read 2 more answers

Students in Mrs. Becker's class and Mr. Rolland's class sold boxes of popcorn for

saveliy_v [14]

Answer:

Please write the question in a more simple form wheras it shall be easier to answer.

Step-by-step explanation:

4 0

4 years ago

The head librarian at the Library of Congress has asked her assistant for an interval estimate of the mean number of books check

Verdich [7]

Answer:

$n=(\frac{1.960(150)}{90})^2 =10.67 \approx 11$

So the answer for this case would be n=11 rounded up to the nearest integer

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)

$\sigma =150$ 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:

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

The confidence interval for this case is given by: (740, 920)

We can find the estimate for the mean and we got:

$\bar X = \frac{740+920}{2} = 830$

and the margin of error is given by :

$ME = \frac{920-740}{2}= 90$

The margin of error is given by this formula:

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

And on this case we have that ME =90 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

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

The critical value for 95% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.025;0;1)", and we got $z_{\alpha/2}=1.960$ , replacing into formula (b) we got:

$n=(\frac{1.960(150)}{90})^2 =10.67 \approx 11$

So the answer for this case would be n=11 rounded up to the nearest integer

5 0

3 years ago

Can somebody help solve either of these?

Leya [2.2K]

First one:
The circumference of the whole circle is (2π x the radius),
and 60° is (60/360) = 1/6 of the whole circumference.

Second one:
The area of the whole circle is (π x the radius²), and
the 40° sector is (40/360) = 1/9 of the whole area.

I hope this is enough help.

8 0

3 years ago