2.1 Assignment*: Z-Scores

What is the symbol for mean?

• $\mu$

• x

• $\sigma$

• $Z$

What is the symbol for an observation or data value?

• $\mu$

• x

• $\sigma$

• $Z$

What is the symbol for z-score?

• $\mu$

• x

• $\sigma$

• $Z$

What is the symbol for standard deviation?

• $\mu$

• x

• $\sigma$

• $Z$

What is the correct formula to find the z-score?

• $x=\frac{z-\mu}{\sigma}$

• $z=\frac{x-\mu}{\sigma}$

• $z=\frac{\mu-x}{\sigma}$

• $z=\frac{\sigma-\mu}{x}$

Find the z-score for a data value of 60, when mean = 50 and standard deviation = 4.

• z = -2.5

• z = 0

• z = 2

• z = 2.5

Find the z-score for a data value of 44, when mean = 44 and standard deviation = 1.

• z = 1

• z = 0

• z = -1.5

• z = 1.5

A set of test scores was found to have a mean of 75 and a standard deviation of 5. What is your z-score if you scored an 83?

• z = -3

• z = -1

• z = 1.6

• z = 2.4

Find the z-score.

The mean speed of a car is 55 mph with a standard deviation of 2. What is the z-score for a car going 70 mph?

(a)  

Tori has a z-score of 2.5 and Alexis has a z-score of 1, which is a "better" score and why?

• Tori because her z-score is more positive.

• Alexis because her z-score is closer to zero.

• Tori because her z-score is closer to zero.

• Alexis because her z-score is more positive.