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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

Which sets does square 7 belong to.

horsena [70]

Answer:Number Sets. There are sets of numbers that are used so often they have special names and symbols: ... The numbers you can make by dividing one integer by another (but not dividing by zero). In other words ... If you square a real number you always get a positive, or zero, result. ... x + 7 = 0, x = −7, Integers, set integer.

Step-by-step explanation:

5 0

3 years ago

It says ( Find the length of the hypotenuse ) ~ Pls? Thanks!

Mashcka [7]

Answer:

5

Step-by-step explanation:

In order to solve this problem, we need to use Pythagorem Theorem (a^2+b^2=c^2)

When using the pythagorem theorem the hypoteneuse would be the c^2 and the two other sides would be a and b (the order doesn't matter).

So, our formula would be:

4^2+3^2=c^2

Simplifies into:

25=c^2

In order to remove the exponent 2, we would have to square root both sides by 2. After doing so, you get the answer 5.

Hope this helps! :)

5 0

3 years ago

Read 2 more answers

What's the anwser to 1+(2)(3)(4)=

AnnyKZ [126]

Answer:

25

Step-by-step explanation:

You start by multiplying 2*3*4 which gives you 24, then you add 1 to that, which is 25.

7 0

3 years ago

Read 2 more answers

6 4/5+5 3/10 adding and subtracting mixed number

lawyer [7]

Too add mixed numbers, first convert them to improper fractions:

34/5 + 53/10

Next, find a common denominator, which in this case is 10.

Convert 34/5 so that it has a denominator of 10 by multiplying the ENTIRE fraction by 2: 68/10

68/10 + 53/10 = 121/10

You can either give your answer in the form of an improper fraction: 121/10, or a mixed number 12 1/10

4 0

3 years ago