Empirical Rule 2025

Front

What shape is a normal distribution curve?

Back

bell curve

Front

If the mean life of a tire is 30,000 km and the standard deviation is 2000 km, what is the range for 68% of all tires?

Back

28,000 km and 32,000 km.

Front

In a normal distribution with a mean of 38 and a standard deviation of 4, what proportion of golfers are between 30 and 46 years old?

Back

95%

Front

In a factory, if the weight of concrete poured follows a normal distribution with a mean of 1150 pounds and a standard deviation of 22 pounds, what is the weight interval for 95% of molds?

Back

1106 to 1194 pounds

Front

What percentage of students pass a test if the mean score is 42% and the standard deviation is 8%, assuming normal distribution?

Back

16%

Front

What is the Empirical Rule?

Back

The Empirical Rule states that for a normal distribution, approximately 68% of data falls within one standard deviation of the mean, 95% within two standard deviations, and 99.7% within three standard deviations.

Front

Define standard deviation in the context of a normal distribution.

Back

Standard deviation measures the amount of variation or dispersion of a set of values in a normal distribution.

Front

What percentage of data falls within one standard deviation of the mean in a normal distribution?

Back

68%

Front

What percentage of data falls within two standard deviations of the mean in a normal distribution?

Back

95%

Front

What percentage of data falls within three standard deviations of the mean in a normal distribution?

Back

99.7%