2.1-2.3 Flashcard Review

Front

If a density curve is symmetrical, then...

Back

The mean is generally equal to the median.

Front

What is the PERCENTILE for the data value of 20 in the given data set?

Back

27th percentile.

Front

Find the z-score of 0.3 if mean=0.15 and SD=0.25 (Round to the first decimal place).

Back

0.6

Front

The sign of the z-score indicates whether the location is above (positive) or below (negative) the mean. True or False?

Back

True.

Front

The density curve shown takes the value 0.5 on the interval 0 ≤ x ≤ 2. What percent of the observations are less than 1?

Back

50%.

Front

Define a density curve.

Back

A density curve is a graph that shows the probability distribution of a continuous random variable.

Front

What does the area under a density curve represent?

Back

The total probability of all outcomes, which equals 1.

Front

How do you calculate the z-score?

Back

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

The value is above the mean.

Front

What does a negative z-score indicate?

Back

The value is below the mean.