PS_Unit 3_Normal Distribution, Z-Scores, & Standardization

What are the defining characteristics of a standard normal distribution?

• Mean of 1, standard deviation of 0

• Mean of 0, standard deviation of 1

• Mean of 0, standard deviation of 0

• Mean of 1, standard deviation of 1

What does a Z-score of -2 indicate about an observation?

• The observation is 2 units to the right of the mean.

• The observation is 2 standard deviations to the left of the mean.

• The observation is 2 standard deviations to the right of the mean.

• The observation is 2 units to the left of the mean.

Which formula is used to calculate a Z-score for an observation (X) from a population with mean (μ) and standard deviation (σ)?

• Z = (μ - X) / σ

• Z = (X + μ) / σ

• Z = (X - μ) / σ

• Z = (X - σ) / μ

A chemistry exam followed a normal distribution with a mean of 60 and a standard deviation of 10. What proportion of students scored less than 49 on the exam?

• 0.8643

• 0.1357

• 0.0256

• 0.7157

How do you find the probability BETWEEN 2 scores?

• Find the probability of each and write as an inequality.

• Find the probability of each and add them together.

• Find the probability of each and subtract them.

• No possible