Statistics and Probability - Lesson 3

What is skewness a measure of in a probability distribution of a random variable?

• Mean

• Median

• Symmetry

• Mode

In a negatively-skewed distribution, where is the distribution concentrated?

• Right side

• Middle

• Both sides

• Left side

What is the shape of a normal distribution curve?

• Sine wave

• Triangle

• Straight line

• Bell-shaped

What is the total area under the normal curve equal to?

• 10

• 2

• 1

• 0.5

What is the standardized form of a Normal Distribution Variable called?

• X-score

• Z-score

• Y-score

• W-score

What is the maximum point on the normal curve?

• Mode

• Median

• Mean

• Standard Deviation

What does a z-score represent in a normal distribution?

• Population percentage

• Total area under the curve

• Raw score

• Number of standard deviations from the mean

What percentage of the data falls below a z-score of -2.08?

• 1.88%

• 2.08%

• 18.8%

• 20.8%

What is the area under the normal curve between the scores 98 and 161?

• 0.3488

• 0.7500

• 0.6512

• 0.5000

What is the area above the score 99 in a normal distribution with mean 75 and standard deviation 15?

• 0.8413

• 0.3413

• 0.1587

• 0.5000