Which of the following shapes is not a polygon

A random survey of 1000 students nationwide showed a mean ACT score of 21.1. Ohio was not used. A survey of 500 randomly selecte

vodka [1.7K]

Answer:

We conclude that the mean Ohio score is below the national average.

Step-by-step explanation:

We are given that a random survey of 1000 students nationwide showed a mean ACT score of 21.1. Ohio was not used.

A survey of 500 randomly selected Ohio scores showed a mean of 20.8. The population standard deviation is 3.

Let $\mu$ = mean Ohio scores.

So, Null Hypothesis, $H_0$ : $\mu$ $\geq$ 21.1 {means that the mean Ohio score is above or equal the national average}

Alternate Hypothesis, $H_A$ : $\mu$ < 21.1 {means that the mean Ohio score is below the national average}

The test statistics that would be used here One-sample z test statistics as we know about population standard deviation;

T.S. = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n}}}$ ~ N(0,1)

where, $\bar X$ = sample mean Ohio score = 20.8

$\sigma$ = population standard deviation = 3

n = sample of Ohio = 500

So, test statistics = $\frac{20.8-21.1}{\frac{3}{\sqrt{500}}}$

= -2.24

The value of z test statistics is -2.24.

Now, at 0.1 significance level the z table gives critical value of -1.2816 for left-tailed test. Since our test statistics is less than the critical values of z as -2.24 < 1.2816, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that the mean Ohio score is below the national average.

4 0

4 years ago

SCATTER PLOTS AND TREND LINES

Fed [463]

•cccccccccccccccccccccccccc

4 0

3 years ago

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If a temperature in degrees Celsius is given as C, finding the sum of 1.8 times C and 32 gives the temperature in degrees Fahren

Yuki888 [10]

Answer:

hsuvsjvBcsjfbdkchdkksfsnadeolataogzfdkgcjb

6 0

3 years ago

Three stamps can be attached to each other in various ways.how many ways might three stamps be attached?

ivanzaharov [21]

Let's call the stamps A, B, and C. They can each be used only once. I assume all 3 must be used in each possible arrangement.
There are two ways to solve this. We can list each possible arrangement of stamps, or we can plug in the numbers to a formula.
Let's find all possible arrangements first. We can easily start spouting out possible arrangements of the 3 stamps, but to make sure we find them all, let's go in alphabetical order. First, let's look at the arrangements that start with A:
ABC
ACB
There are no other ways to arrange 3 stamps with the first stamp being A. Let's look at the ways to arrange them starting with B:
BAC
BCA
Try finding the arrangements that start with C:
C_ _
C_ _
Or we can try a little formula; y×(y-1)×(y-2)×(y-3)...until the (y-x) = 1 where y=the number of items.
In this case there are 3 stamps, so y=3, and the formula looks like this: 3×(3-1)×(3-2).
Confused? Let me explain why it works.
There are 3 possibilities for the first stamp: A, B, or C.
There are 2 possibilities for the second space: The two stamps that are not in the first space.
There is 1 possibility for the third space: the stamp not used in the first or second space.
So the number of possibilities, in this case, is 3×2×1.
We can see that the number of ways that 3 stamps can be attached is the same regardless of method used.

8 0

3 years ago

Select the correct answer. Which statement is true?

dusya [7]

Answer:

third option is the correct

Step-by-step explanation:

A function is "odd" when f (-x) = - f (x) for all x. ... For example, functions like

f (x) = x3,
f (x) = x5,
f (x) = x7, ... are odd functions.

6 0

3 years ago

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