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There is a linear relationship between the number of chirps made by the striped ground cricket and the air temperature. A least squares fit ofsome data collected by a biologist gives the model y= 25.2 + 3.3x, 9 < x < 25, where x is the number of chirps per minute and y is the estimatedtemperature in degrees Fahrenheit. What is the estimated increase in temperature that corresponds to an increase in 5 chirps per minute?

User MrUser
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25 votes
25 votes

The given model is:


\begin{gathered} y=25.2+3.3x \\ 9Where y is the estimated temperature (F) and x is the number of chirps per minute.<p>To estimate the increase in the temperature that corresponds to an increase in 5 chirps per minute, we need to find the estimated temperature before and after the increase in chirps, so, let's assume the initial number of chirps per minute is 10 (it has to be in the domain of the function 9[tex]\begin{gathered} y=25.2+3.3\cdot10 \\ y=25.2+33 \\ y=58.2\text{ F} \end{gathered}Now, an increase of 5 chirps will let us to 10+5=15 chirps per minute, and the temperature will be:


\begin{gathered} y=25.2+3.3\cdot15 \\ y=25.2+49.5 \\ y=74.7\text{ F} \end{gathered}

The estimated increase in temperature is then:


\begin{gathered} \text{Increase}=\text{ final temperature - initial temperature} \\ \text{Increase}=74.7F-58.2F \\ \text{Increase}=16.5F \end{gathered}

The estimated increase in temperature that corresponds to an increase in 5 chirps per minute is 16.5 °F

User Irbis
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