Use the Empirical Rule to Solve the Problem

question 28

Multiple Choice

Use the empirical rule to solve the problem.
-The lifetimes of lightbulbs of a particular type are normally distributed with a mean of 400 hours and a standard deviation of 12 hours. What percentage of the bulbs have lifetimes that lie within 2 Standard deviations to either side of the mean?

• A)97.72%
• B)99.74%
• C)95.44%
• D)68.26%

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Definitions:

Population Size

The total number of individuals within a species that occupy a particular geographic area.

Genetic Drift

A mechanism of evolution that causes allele frequencies within a population to change randomly with time due to chance events.

Natural Selection

A process by which species evolve over time as individuals with traits more suited to their environment are more likely to survive and reproduce.

Adaptive Evolution

The process through which populations become better suited to their environment through changes in genetic traits.