Three Defective Electric Toothbrushes Were Accidentally Shipped to a Drugstore

question 110

Multiple Choice

Three defective electric toothbrushes were accidentally shipped to a drugstore by the manufacturer along with 17 non-defective ones. What is the probability that the first two electric toothbrushes sold will be returned to the drugstore because they are defective?

• A) 3/20 or 0.15
• B) 3/17 or 0.176
• C) 1/4 or 0.25
• D) 3/190 or 0.01579

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Definitions:

Income

Money that an individual or business receives, typically in exchange for providing a good or service, or through investing.

Slope

In mathematics, the rate at which a line inclines or declines, indicating the steepness of the line.

Regression Line

A straight line that describes how a response variable Y changes as an explanatory variable X changes, used in linear regression.

Least Squares Regression Line

A straight line that minimizes the sum of the squared differences between the observed values and the values predicted by the line.