Question

problem

1. draw a line of best fit in the scatter plot above. what is the equation of the line of best fit?

work
answer
y = 10x + 360
green
y = -5x + 380
blue
y = -20x + 400
white

1. use the equation to determine how many hot chocolates they can expect to sell at the concession stand on a day with a low temperature of 45°f.

155 hot chocolates
purple
125 hot chocolates
red
275 hot chocolates
orange

1. use the equation to determine what the low temperature will likely be on a day where 100 hot chocolates are sold.

66°f
pink
61°f
orange
56°f
yellow
© miss math lady (cassie f

Explanation:

Problem 8

Step1: Analyze scatter plot trend (implied)

Assume negative correlation (hot chocolate sales vs temp), so slope negative.

Step2: Check slopes

Green: \(10\) (positive, out). Blue: \(-5\), White: \(-20\). Likely moderate negative, so \(y = -5x + 380\) (blue) fits better (steeper \(-20\) less likely for typical scatter).

Step1: Use equation \(y = -5x + 380\) (from Q8)

Substitute \(x = 45\) (temp) into \(y = -5x + 380\).

Step2: Calculate

\(y = -5(45) + 380 = -225 + 380 = 155\).

Step1: Use \(y = -5x + 380\), solve for \(x\) when \(y = 100\)

\(100 = -5x + 380\).

Step2: Solve for \(x\)

\(-5x = 100 - 380 = -280\) → \(x = \frac{-280}{-5} = 56\).

Answer:

B. \(y = -5x + 380\) (blue)

Problem 9