Chapter 3, Problem 9PT

To determine

To find: the predicted increase in temperature if 5 chirps increase per minute

Answer to Problem 9PT

Option (b) is the correct one.

Explanation of Solution

Given:

  $\widehat{y}=25.2+3.3x$

(a) 13°F

(c) 25.2°F

(e) 41.7°F

(b) 16.5°F

(d) 28.5°F

Calculation:

Here x is the number of chirps per minute and $\widehat{y}$ is the estimated temperature in degrees Fahrenheit.

According to the definition of slope, b. there will be 3.3 units of change in temperature for a unit increment in number of chirps per minute.

Suppose there is an increase of 5 chirps per minute.

We know that, for a unit increment there will be 3.3 units of increment in temperature. Then for 5 units of increment in X values, there will be $5\times 3.3$ units of increment in Y values.

That is, the predicted increase in temperature for an increase of 5 chirps per minute will be$\begin{array}{c}5b=5\times 3.3\\ =16.5°F\end{array}$

Conclusion:

Therefore, the predicted increase in temperature is 16.5°F