00:01
So in this question, they say that the stopping distance of an automobile on dry level pavement, traveling at a speed v in kilometers per hour, is the distance are in meters that the car travels during the reaction time of the driver, plus the distance b in meters that the car travels after the brakes are applied see the figure.
00:22
The table shows the results of the experiment, and we will round our coefficients to three decimal places.
00:28
In part a, they say, i want to use the regrettable.
00:31
Capabilities of a graphing utility to find a linear model for the reaction time distance r.
00:39
So i'm going to head to my calculator and i'm going to go into my stat and i'm going to edit.
00:47
I'm going to clear out what i have in l1 and l2.
00:55
Now in l1 i'm going to put my x values, which are my speeds this time.
01:01
They're 20, 40.
01:05
60, 80, and 100.
01:11
And in l2, i'm going to put my values of r.
01:14
So 7 .6, 16, 24 .3, 32 .6, and 41.
01:28
Once i've done so, i'm going to go to stat again, and i'm going to calculate a linear regression on the data set that's in l1 and l2.
01:38
I calculate, and what am i getting? i'm getting .417x minus .72.
01:47
So here i'm getting, i'm going to use v instead of x, but i'm getting 0 .417v, and then this was plus b, which is negative 0 .72, so minus 0 .72.
02:04
In part b, use the regression capabilities of a graphing utility to find a quadratic model for the breaking distance b, again rounding our numerical values to four decimal places.
02:18
So i'm going back to my calculator, and now i'm going to say going back to stat, i'm going to edit, and in l2, i'm going to have 1 .6, i'm going to have 8 .3, 19 .5, 35 .1 .1.
02:37
And 55 .2.
02:43
And what do i do? i'm going to quit.
02:45
I'm going to stat calculate a quadratic regression on l1 and l2...