kennedy has a part - time job at an ice skating rink selling hot cocoa. she decided to plot the number of…
kennedy has a part - time job at an ice skating rink selling hot cocoa. she decided to plot the number of hot cocoas she sold relative to the days high temperature and then draw the line of best fit. based on the line of best fit, how many hot cocoas would you predict kennedy to sell if the days high temperature were 40°f?
Answer
Explanation:
Step1: Find the slope of the line
Use two - points $(0,84)$ and $(24,63)$ on the line of best - fit. The slope formula is $m=\frac{y_2 - y_1}{x_2 - x_1}$. $m=\frac{63 - 84}{24-0}=\frac{- 21}{24}=-\frac{7}{8}$
Step2: Find the y - intercept
The y - intercept $b$ is the value of $y$ when $x = 0$. From the point $(0,84)$, $b = 84$. The equation of the line in slope - intercept form is $y=mx + b$, so $y=-\frac{7}{8}x + 84$.
Step3: Predict the number of hot cocoas
We want to find $y$ when $x = 40$. Substitute $x = 40$ into the equation $y=-\frac{7}{8}\times40+84$. First, calculate $-\frac{7}{8}\times40=-35$. Then $y=-35 + 84=49$.
Answer:
49