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a researcher studied the relationship between the number of times a certain species of cricket will chirp in one minute and the temperature outside. her data is expressed in the scatter plot and line of best fit below. what does the slope of the line represent?
(scatter plot with x - axis chirps per minute and y - axis temperature (degrees fahrenheit))
answer
how long the cricket continues to chirp.
the expected change in temperature in degrees fahrenheit for each additional cricket chirp in one minute.
the expected change in number of cricket chirps in one minute for each additional degree fahrenheit.
the expected temperature when the cricket chirps a time.
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Explanation:

To determine what the slope of the line of best fit represents, we analyze the variables: the x - axis is "Chirps Per Minute" and the y - axis is "Temperature (Degrees Fahrenheit)". The slope of a line in a scatter plot with a line of best fit is calculated as $\frac{\text{change in }y}{\text{change in }x}$. Here, $y$ is temperature and $x$ is the number of chirps per minute. So the slope represents the expected change in the $y$ - variable (temperature) for each unit change in the $x$ - variable (number of chirps per minute).

Let's analyze each option:

• "How long the cricket continues to chirp": The slope has nothing to do with the duration of chirping, so this is incorrect.
• "The expected change in number of cricket chirps in one minute for each additional degree Fahrenheit": This would be the reciprocal of the slope (since it's change in $x$ over change in $y$), so this is incorrect.
• "The expected change in temperature in degrees Fahrenheit for each additional cricket chirp in one minute": This matches the interpretation of the slope ($\frac{\text{change in temperature}}{\text{change in chirps per minute}}$), so this is correct.
• "The expected temperature when the cricket chirps a time": This describes the y - intercept (the value of $y$ when $x = 0$), not the slope, so this is incorrect.

Answer:

The expected change in temperature in degrees Fahrenheit for each additional cricket chirp in one minute.