z-score practice

Front

What is a z-score?

Back

A z-score indicates how many standard deviations an element is from the mean. It is calculated using the formula: z = (X - μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation.

Front

How do you calculate a z-score?

Back

To calculate a z-score, use the formula: z = (X - μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation.

Front

What does a positive z-score indicate?

Back

A positive z-score indicates that the value is above the mean.

Front

What does a negative z-score indicate?

Back

A negative z-score indicates that the value is below the mean.

Front

If the mean waist size is 29 inches and the standard deviation is 2 inches, what is the z-score for a waist size of 33 inches?

Back

z = (33 - 29) / 2 = 2.

Front

If Jane's z-score is 1.2 on a test with a mean of 100 and a standard deviation of 15, what is her score?

Back

X = μ + z * σ = 100 + 1.2 * 15 = 118.

Front

What is the z-score for a temperature of 17 degrees if the mean is 23 degrees and the standard deviation is 4.2 degrees?

Back

z = (17 - 23) / 4.2 = -1.43.

Front

If Jeannie's z-score is 2.56 and the mean height for women is 63.6 inches with a standard deviation of 2.5 inches, what is her height?

Back

X = μ + z * σ = 63.6 + 2.56 * 2.5 = 70 inches.

Front

What is the z-score for a dairy product with a shelf life of 17 days, given a mean of 12 days and a standard deviation of 3 days?

Back

z = (17 - 12) / 3 = 1.6667.

Front

What is the mean in a normal distribution?

Back

The mean is the average value of a dataset, which is the center point of a normal distribution.