Question

This table shows the rainfall (in centimeters) for a city in different months. The quadratic regression equation that models these data is y=-0.77x^2+6.06x - 5.9Using this model, the predicted rainfall for month 11 is about -32.4 centimeters. Does this prediction make sense? Why or why not?A. No, because you can’t have a negative amount of rainfall.B. Yes, because the rainfall is declining.C. Yes, because it is the result of substituting x=11D. No, because you can’t measure rainfall in centimeters

Answer 1

The quadratic regression equation model given is;

`\begin{gathered} y=-0.77x^2+6.06x-5.9 \\ \text{where y is the rainfall measure in cm} \\ x\text{ is the month} \end{gathered}`

For month 11, substituting x = 11 in the equation,

The predicted rainfall in month 11 is -32.4cm

From the options given, the correct answer is option A because the prediction does not make sense because there can not be a negative amount of rainfall.

Therefore, option A is the right answer.