Question 1

Given the TI-84 screen display, what is the correct formula for calculating the sample mean $$\bar{x}$$ using the values shown?

Accepted Answer

$$\bar{x} = \frac{\sum x}{n}$$

Question 2

If the data shown is from a population, which symbol should be used for the mean?

Accepted Answer

$$\mu$$

Question 3

What is the value of the sample standard deviation $$s as $$shown on the TI-84 display?

Accepted Answer

$$s = 15.93942783$$

Question 4

Which formula is used to calculate the population variance $$\$$sigma^2$$?

Accepted Answer

$$\$$sigma^2$$ = \frac{\sum (x - \mu)^2$}{N}$$

Question 5

If the data is from a sample, which symbol should be used for the standard deviation?

Accepted Answer

$$s$$

Question 6

What is the interquartile range (IQR) given $$Q_1 = 19$ and if Q_3$ = 45$$?

Accepted Answer

$$IQR = Q_3$ - Q_1$ = 45 - 19 = 26$$

Question 7

Which value represents the minimum in the data set as shown on the TI-84 display?

Accepted Answer

$$	ext{minX} = 12$$

Question 8

If you are asked to find the sample variance $$s^2$$ using the sample standard deviation $$s = 15.93942783$$, what is the correct calculation?

Accepted Answer

$$s^2$$ = $$(15.93942783)^2$$

Question 9

Which symbol is used for the summation of all x-values in a data set?

Accepted Answer

$$\sum x$$

Question 10

If the data is from a population, which formula should be used to calculate the population standard deviation $$\sigma$$?

Accepted Answer

$$\sigma = \sqrt{\frac{\sum (x - \mu)^2$}{N}}$$

Question 11

What is the correct interpretation of $$Q_1 as $$shown on the TI-84 display?

Accepted Answer

$$Q_1 is $$the first quartile, representing the value below which 25\% of the data falls.

Question 12

Which symbol is used for the sample size in statistics?

Accepted Answer

$$n$$

Question 13

If the data set has $$n = 18$$ and $$\sum x = 598$$, what is the sample mean $$\bar{x}$$?

Accepted Answer

$$\bar{x} = \frac{598}{18} = 33.22222222$$

Question 14

Which value on the TI-84 display represents the population standard deviation?

Accepted Answer

$$\sigma_x = 15.49033948$$

Question 15

If you are given $$\sum x^2$ = 24186$$ and $$n = 18$$, which formula would you use to calculate the sample variance $$s^2$$?

Accepted Answer

$$s^2$$ = \frac{\sum $$x^2$$ - \frac{(\sum $$x)^2$$}{n}}{n-1}$$

Question 16

Which symbol is used for the population size?

Accepted Answer

$$N$$

Question 17

If the data is from a sample, which formula should be used to calculate the sample standard deviation $$s$$?

Accepted Answer

$$s = \sqrt{\frac{\sum (x - \bar{x})^2$}{n-1}}$$

Question 18

What is the correct formula for the interquartile range (IQR)?

Accepted Answer

$$IQR = Q_3$ - Q_1$

Question 19

Which symbol is used for the sample variance?

Accepted Answer

$$s^2$$

Question 20

If you are asked to find the median, which symbol should you use?

Accepted Answer

$$Q_2$$

Statistical Symbols and Calculator Output Interpretation (Chapters 1–3)

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