Chapter 4, Problem 50SGR

To determine

To Find:

An equation of the regression line and estimate the daily ticket sales on the 15^th day after the movie opens.

Answer to Problem 50SGR

The regression equation is :

  $y=-5.79x+99.14$

The ticket sales on 15^th day after the movie open = $12.29

Explanation of Solution

Given Information:

The table shows ticket sales during the first week.

  

Calculation:

Let

x -axis = days since movie opened

y -axis = daily ticket sales ($)

Using the regression calculator to find the equation of the regression line :

Days since sale began (x)	Daily Sales (y)
1	85
2	92
3	89
4	78
5	65
6	68
7	55

Calculation Summary

  

  

So, the regression equation is :

  $y=-5.79x+99.14$

Substituting the value of x =15 in regression equation to find the ticket sales on day 15 after the movie open :

  $\begin{array}{l}y=-5.79+99.14\\ y=-5.79(15)+\mathrm{99.14.....................}[x=15]\\ y=-86.85+99.14\\ y=12.29\end{array}$

So, the ticket sales on 15^th day after the movie open = $12.29