Chapter 4.5, Problem 29E

(a)

To determine

To predict: The total number of people reported

Answer to Problem 29E

The total number of people reported an earthquake $9$ minutes = $2863$

The total number of people reported an earthquake $15$ minutes = $5149$

Explanation of Solution

Given:

Minutes, x	$9$	$15$
People, y	$2750$	$3200$

Calculation:

Substituting $x=9$ and $x=15$ in the equation $y=381x-566$

  $\begin{array}{l}y=381x-566\\ =3429-566\\ =2863\\ y=381(15)-566\\ =5715-566\\ =5149\end{array}$

Therefore, using the model $y=381x-566$ from exercise $17$ ,

The total number of people reported an earthquake $9$ minutes = $2863$

The total number of people reported an earthquake $15$ minutes = $5149$

Conclusion:

Therefore, the total number of people reported an earthquake $9$ minutes = $2863$

The total number of people reported an earthquake $15$ minutes = $5149$

(b)

To determine

To describe: The accuracy of the extrapolations

Answer to Problem 29E

The second prediction was less accurate than the first

Explanation of Solution

Given:

Minutes, x	$9$	$15$
People, y	$2750$	$3200$

Calculation:

The difference between the first extrapolation and the actual data value is only $113$ . The difference between the second extrapolation and the actual data value is $1949$

So, the second prediction was less accurate than the first. This fits what you would expect because the farter removed a value if from the known values, the less confidence you can have in the accuracy of prediction

Conclusion:

The second prediction was less accurate than the first