Part 2 - Find the error(s) and solve the problem correctly.

g A random sample of 100 students was taken. Eighty-five of the student in the sample experienced anxiety during the exam. We ar

BaLLatris [955]

Answer:

The test statistic is $z = 1.25$

Step-by-step explanation:

We are interested in determining whether or not the proportion of the student who experience anxiety during the exam is significantly more than 80%.

At the null hypothesis, we test if the proportion is 80%, that is:

$H_0: p = 0.8$

At the alternate hypothesis, we test if the proportion is more than 80%, that is:

$H_a: p > 0.8$

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, $\sigma$ is the standard deviation and n is the size of the sample.

80% is tested at the null hypothesis:

This means that $\mu = 0.8, \sigma = \sqrt{0.2*0.8} = 0.4$

A random sample of 100 students was taken. Eighty-five of the student in the sample experienced anxiety during the exam.

This means that $n = 100, X = \frac{85}{100} = 0.85$

The test statistic is

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{0.85 - 0.8}{\frac{0.4}{\sqrt{10}}}$

$z = 1.25$

The test statistic is $z = 1.25$

4 0

3 years ago

You spin each spinner once. You get $50 if you spin a 2 and a vowel. You get $25 if you spin a 2 and a consonant. You get $5 if

Tom [10]

The expected value of the game is $8.75.

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The expected value is the sum of each outcome multiplied by it's probability.
A probability is the number of desired outcomes divided by the number of total outcomes.

The probability of spinning a 2 and a vowel is: $\frac{1}{4} \times \frac{2}{8} = \frac{2}{32}$ .
Thus, $\frac{2}{32}$ probability of getting $50.

The probability of spinning 2 and a consonant is: $\frac{1}{4} \times \frac{6}{8} = \frac{6}{32}$

Thus, $\frac{6}{32}$ probability of getting $25.

The probability of spinning 1 and a vowel is: $\frac{3}{4} \times \frac{2}{8} = \frac{6}{32}$ .
Thus, $\frac{6}{32}$ probability of getting $5.