company x tried selling widgets at various prices to see how much profit they would make. the following…

company x tried selling widgets at various prices to see how much profit they would make. the following table shows the widget selling price, x, and the total profit earned at that price, y. write a quadratic regression equation for this set of data, rounding all coefficients to the nearest hundredth. using this equation, find the profit, to the nearest dollar, for a selling price of 11.25 dollars.\n\n| price (x) | profit (y) |\n| ---- | ---- |\n| 11.00 | 3948 |\n| 13.50 | 5773 |\n| 18.50 | 7865 |\n| 25.75 | 7815 |\n| 30.00 | 5611 |
Answer
Answer:
Regression Equation: $y = - 10.37x^{2}+561.98x - 1989.37$ Final Answer: $4107$
Explanation:
Step1: Enter data into calculator
Enter the price - profit data pairs into a statistics calculator.
Step2: Perform quadratic regression
Use the quadratic regression function on the calculator. It will find the coefficients $a$, $b$, and $c$ for the quadratic equation $y = ax^{2}+bx + c$. After calculation, $a\approx - 10.37$, $b\approx561.98$, $c\approx - 1989.37$.
Step3: Substitute $x = 11.25$
Substitute $x = 11.25$ into the equation $y=-10.37x^{2}+561.98x - 1989.37$. $y=-10.37\times(11.25)^{2}+561.98\times11.25-1989.37$. $y=-10.37\times126.5625 + 6312.275-1989.37$. $y=-1312.453125+6312.275 - 1989.37$. $y = 4107.451875\approx4107$.