Question

The table shows the temperature (in degrees) for eight consecutive days as well as the respective number of ice cream cones an ice cream shop sold on each of these days.
Temperature: 68, 77, 83, 85, 89, 94, 96, 99
number of cones: 403, 447, 457, 465, 489, 503, 543, 576

About how many ice cream cones woud you expect the shop to sell if the temperature one day is 106 degrees? Find a line of best fit for this data and use it to make your prediction.

A. 579
B. 585
C. 602
D. 617

Answer 1

Answer:

B. 585

Step-by-step explanation:

A graph of the scatter plot and line of best fit is attached.

The temperature in this problem will be the independent variable, or x.  This is because we are assuming that the number of ice cream cones sold depends on the temperature; this means the number of ice cream cones will be the dependent variable, or y.

This means in our graphing calculator, we will enter temperature in the first list and the number of cones in the second.

After drawing the scatter plot, we run the linear regression; we get the values for a and b in our equation, y = ax+b:

a = 5.08

b = 46.59

This gives us the equation y = 5.08x + 46.59.

Entering our temperature, 106, in for x gives us

y = 5.08(106) + 46.59 = 585.07 ≈ 585