### Sample of Scores, Measure of Central Tendency, Frequency Distribution Table,

Measure Of Central Tendency, Distribution, Frequency Distribution Table, Sample, Mean, Population, Normal Distribution, Median, Distribution of Scores, Sample of Scores, Population Mean, Balance Point, Distribution of Scores, Correlation.

What is the mean for the following sample of scores? Scores: 1, 4, 5, 6

**4**

A population of n = 8 scores has EX = 40. What is the population mean?

**5**

What is the mean for the population of scores shown in the frequency distribution table?

X f

5 2

4 1

3 3

2 2

1 2

**29/10 = 2.90**

A sample has a mean of M = 90. If each score in the sample is multiplied by 5, then what is the mean for the new distribution?**450**

Which of the following actions will always change the value of the mean?

**Changing the value of one score**

The mean is considered to the “balance point” for a distribution because exactly half of the scores are located above the mean and exactly half are below the mean.

**False**

Adding a new score to a distribution will always change the value of the mean.

**False**

Changing the value of a score in a distribution will always change the value of the mean.

**True**

What is the value of the median for the following set of scores? Scores: 1, 3, 4, 6, 8, 12, 13, 23, 25, 26

**10**

What is the median for the following set of scores? Scores: 1, 2, 6, 11, 17**6 **

What is the median for the population of scores shown in the frequency distribution table?

X f

5 1

4 2

3 3

2 4

1 2

**2.5**

Which of the following statements cannot be true for a distribution of scores?

a) 60% of the scores are above the mean

b) 60% of the scores are above the median

c) 60% of the scores are above the mode**d) all of the other options are false statements**

For a 100-point exam, a score of X = 65 is definitely above the median.

**False**

What is the mean for the following sample of scores? Scores: 1, 4, 5, 6

**4**

A population of n = 8 scores has EX = 40. What is the population mean?

**5**

What is the mean for the population of scores shown in the frequency distribution table?

X f

5 2

4 1

3 3

2 2

1 2

**29/10 = 2.90**

A sample has a mean of M = 90. If each score in the sample is multiplied by 5, then what is the mean for the new distribution?**450**

Which of the following actions will always change the value of the mean?

**Changing the value of one score**

The mean is considered to the “balance point” for a distribution because exactly half of the scores are located above the mean and exactly half are below the mean.

**False**

Adding a new score to a distribution will always change the value of the mean.

**False**

If a sample has an odd number of scores, at least one individual will have a score exactly equal to the median.

**True**

What is the mode for the following sample of n = 8 scores? Scores: 0, 1, 1, 1, 2, 2, 3, 3

**1**

Which of the following statements cannot be true for a distribution of scores?

**no one has a score exactly to the mode**

Which of the following statements is true?

a) it is possible for a distribution to have two means

b) it is possible for a distribution to have two medians**c) it is possible for a distribution to have two modes**

d) it is possible for a distribution to have two medians or two modes

For any distribution of scores, at least one individual will have a score exactly equal to the mean.

**False**

It is possible for a distribution to have more than one mode.

**True**

It is possible to have a distribution of scores where no individual has a score exactly equal to the mode.

**False**

A researcher measures eye color for a sample of n = 50 people. Which measure of central tendency would be appropriate to summarize the measurements?

a) mean

b) median**c) mode**

d) any of the three measure could be used

A researcher is measuring the amount of time needed to solve a set of anagrams for a sample of n = 15 students. However, one of the participants fails to solve the problems so the researcher has an undetermined score. What is the best measure of central tendency for these data?

a) the mean**b) the median**

c) the mode

d) central tendency cannot be determined for these data

What is the probability of randomly selecting a z-score less than z = +2.25 from a normal distribution?

**p = 0.9878 (body)**

To avoid having her hours cut back at work, Bridgett must avoid performing in the lowest 40% of the distribution of workers at her job. Specifically, typical amount of items manufactured at her job form a normal distribution with µ = 100 and σ = 4. Bridgett needs to manufacture more than _____ items in order to avoid having her hours cut back at work.

**X = 99**

A set of n = 25 pairs of scores ( X and Y values) in a research study has a Pearson correlation of r = 0.80. What percentage of the variance for the Y scores is predicted by its relationship with X?

**64%**

A researcher measures driving distance from college and weekly cost of gas for a group of commuting college students. Which kind of correlation is likely to be obtained for these two variables?

**A positive correlation**

A set of n = 20 pairs of X and Y scores has SS X = 10, SS Y = 40, and SP = 30. What is the slope for the regression equation for predicting Y from X?

**b = 3.00**

A researcher obtains a Pearson correlation of r = 0.60 for a sample of n = 6 pairs of X and Y scores. If the researcher tests the significance of the correlation, which value will be obtained for the t statistic?

**t = 1.50**

A normal distribution has a mean of µ = 40 with σ = 8. If one score is randomly selected from this distribution, which is the probability that the score will be less than X = 34?

**p = 0.2266**

Which proportion of a normal distribution is located between z = 0 and z = +1.50?

**0.4332**

Intelligent quotient (IQ) scores form a normal distribution with µ = 100 and σ = 15. Individuals with IQ scores above 140 are classified in the genius category. Which proportion of the population consists of geniuses?

**0.0038**

A vertical line drawn through a normal distribution at z = -0.60 separates the distribution into two sections, the body and the tail. Which proportion of the distribution is in the body?

**0.7257**

What is the probability of randomly selecting a z-score greater than z = +1.25 from a normal distribution?

**p = 0.1056**

What is the mean for the following sample of scores? Scores: 1, 4, 5, 6

**4**

A population of n = 8 scores has EX = 40. What is the population mean?

**5**

What is the mean for the population of scores shown in the frequency distribution table?

X f

5 2

4 1

3 3

2 2

1 2

**29/10 = 2.90**

A sample has a mean of M = 90. If each score in the sample is multiplied by 5, then what is the mean for the new distribution?**450**

Which of the following actions will always change the value of the mean?

**Changing the value of one score**

The mean is considered to the “balance point” for a distribution because exactly half of the scores are located above the mean and exactly half are below the mean.

**False**

Adding a new score to a distribution will always change the value of the mean.

**False**

Which of the following statements is true?

a) it is possible for a distribution to have two means

b) it is possible for a distribution to have two medians**c) it is possible for a distribution to have two modes**

d) it is possible for a distribution to have two medians or two modes

For any distribution of scores, at least one individual will have a score exactly equal to the mean.

**False**

It is possible for a distribution to have more than one mode.

**True**

It is possible to have a distribution of scores where no individual has a score exactly equal to the mode.

**False**

A researcher measures eye color for a sample of n = 50 people. Which measure of central tendency would be appropriate to summarize the measurements?

a) mean

b) median**c) mode**

d) any of the three measure could be used

A researcher is measuring the amount of time needed to solve a set of anagrams for a sample of n = 15 students. However, one of the participants fails to solve the problems so the researcher has an undetermined score. What is the best measure of central tendency for these data?

a) the mean**b) the median**

c) the mode

d) central tendency cannot be determined for these data