SOLUTION: An experiment examined the relationship between the number of miles a car traveled, y, per gallon of gasoline and the speed of the car, x, in miles per hour. The table displays th

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: An experiment examined the relationship between the number of miles a car traveled, y, per gallon of gasoline and the speed of the car, x, in miles per hour. The table displays th      Log On


   

Question 1206978: An experiment examined the relationship between the number of miles a car traveled, y, per gallon of gasoline and the speed of the car, x, in miles per hour. The
table displays the data collected.
https://ibb.co/TbpbTVh
A quadratic function can be used to model the data in the table. Which value best
estimates the miles per gallon when the speed is 65 miles per hour?
A. 27.9
B. 31.0
C. 40.2
D. 24.9
Found 3 solutions by MathLover1, ikleyn, Edwin McCravy:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

speed,x (mil%2Fh) | mil per gallon, y
20......................|..........24.9
30......................|..........28.3
35......................|..........29.1
40......................|..........30.1
50......................|..........30.0
60......................|..........29.1

use quadratic regression calculator to find the parabola of best fit:

https://www.emathhelp.net/en/calculators/probability-statistics/quadratic-regression-calculator/?xs=20%2C30%2C35%2C40%2C50%2C60&ys=24.9%2C28.3%2C+29.1%2C+30.1%2C30%2C29.1%2C


y=-0.00733766233766234x%5E2%2B0.688662337662338x%2B14.1153246753247
ifx=65
y=-0.00733766233766234%2A65%5E2%2B0.688662337662338%2A65%2B14.1153246753247
y=27.8767532467532835
y=27.9

answer: A

Answer by ikleyn(52754) About Me  (Show Source):
You can put this solution on YOUR website!
.

Quadratic regression can be found using regular calculator TI-83/84.

On how to do it, see textual description in this document

https://bakalyanmath.weebly.com/uploads/5/4/5/6/54569937/doc082117-08212017101249.pdf



Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
On your TI-84

First you must set the Window for the graph

Press WINDOW
Make Xmin read Xmin=-20
Make Xmax read Xmax=120
Make Ymin read Ymin=-10
Make Ymax read Ymax=40
Leave the other values as they are.

Press STAT
Press 1  (for EDIT)
Enter the x-values in L1 and the y-values in L2
Press STAT again
Use right arrow key to highlight CALC.
Press 5 (for QuadReg)
Use down arrow to scroll to Store RegEQ:
Press VARS
Use right arrow key to highlight Y-VARS
Press 1  (for Function...
Press 1  (for Y1)
Press GRAPH
Press 2nd trace
Press 1  (for value)
Make X= under graph read X=65
Press ENTER
See the value of Y
Round to the nearest tenth.

Edwin