Suppose a store manager wants to know the demand y for an energy bar as a function of price x. The daily sales for three different prices of the energy bar are shown in the table. Determine the least squares regression line for the data using the regression capabilities of a graphing utility, and then use this model to estimate the demand when the price is $1.59.
A) 202
B) 166
C) 190
D) 151

Question

Suppose a store manager wants to know the demand y for an energy bar as a function of price x. The daily sales for three different prices of the energy bar are shown in the table. Determine the least squares regression line for the data using the regression capabilities of a graphing utility, and then use this model to estimate the demand when the price is $1.59. 
A) 202 
B) 166 
C) 190 
D) 151

Quizplus · Accepted Answer

Using a graphing utility to find the least squares regression line, we get:
y = -31.21x + 79.06
Using this model to estimate the demand when the price is $1.59:
y = -31.21(1.59) + 79.06 = 166.15
Round to the nearest whole number, the estimated demand is 166. Therefore, the best choice is B.

Suppose a Store Manager Wants to Know the Demand Y