I need help learning how to solve <br> -p-4p>-10

What happens to the standard deviation of the average of a sample as the sample size increases? Group of answer choices It gets

NeX [460]

Answer:

Gets smaller

Step-by-step explanation:

- The standard deviation is the quantification of spread of data. According to descriptive statistics the standard deviation s is given by:

s = Σ ( x - u ) / sqrt ( n )

Where, n : sample size

u : Mean value

- So we see that standard deviation (s) is inversely proportional to square root of sample size (n).

- We can see that as sample size (n) increases the standard deviation (s) decreases.

3 0

3 years ago

Please i need help! :(

stepan [7]

Help help help help help help

5 0

3 years ago

Read 2 more answers

. Exam scores for a large introductory statistics class follow an approximate normal distribution with an average score of 56 an

Andru [333]

Answer:

0.1% probability that the average score of a random sample of 20 students exceeds 59.5.

Step-by-step explanation:

The Central Limit Theorem estabilishes that, for a random variable X, with mean $\mu$ and standard deviation $\sigma$ , a large sample size can be approximated to a normal distribution with mean $\mu$ and standard deviation $\frac{\sigma}{\sqrt{n}}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 56, \sigma = 5, n = 20, s = \frac{5}{\sqrt{20}} = 1.12$

What is the probability that the average score of a random sample of 20 students exceeds 59.5?

This is 1 subtracted by the pvalue of Z when $X = 59.5$ . So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{59.5 - 56}{1.12}$

$Z = 3.1$

$Z = 3.1$ has a pvalue of 0.9990.

So there is a 1-0.9990 = 0.001 = 0.1% probability that the average score of a random sample of 20 students exceeds 59.5.

3 0

3 years ago

Use Euler's formula to write 3+3i^3 in exponential form.

Alex_Xolod [135]

21−=2(2−)=2cos(−1)+2 sin(−1)

−1+2=−1(2)=−1(cos2+sin2)=cos2+ sin2

Is the above the correct way to write 21− and −1+2 in the form +? I wasn't sure if I could change Euler's formula to =cos()+sin(), where is a constant.

complex-numbers

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edited Mar 6 '17 at 4:38

Richard Ambler

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asked Mar 6 '17 at 3:34

14wml

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Add a comment

1 Answer

1

No. It is not true that =cos()+sin(). Notice that

1=1≠cos()+sin(),

for example consider this at =0.

As a hint for figuring this out, notice that

+=ln(+)

then recall your rules for logarithms to get this to the form (+)ln().

8 0

3 years ago

PLEASE HELP!!!!

Valentin [98]

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5 0

3 years ago

I need help learning how to solve -p-4p>-10