Copyright © 2006 Texas Instruments Incorporated 35
Change Anthony’s last score from 11 to 15.
If the teacher adds 4 points to Test 4, Anthony’s average
grade is 12.
³ Problem
The table below gives the results of a braking test.
Use the relationship between speed and braking distance to
estimate the braking distance required for a vehicle traveling
at 55kph.
A hand-drawn scatter plot of these data points suggest a
linear relationship. The TI-30XS MultiView™ calculator uses
the least squares method to find the line of best fit, y'=ax'+b,
for data entered in lists.
v $$$ 15 $
%t1 $$ <
Test No. 1 2 3 4
Speed
(kph) 33 49 65 79
Braking
distance
(m)
5.30 14.45 20.21 38.45
v v 4
33 $49 $ 65 $ 79 $ " 5.3 $
14.45 $ 20.21 $ 38.45 $
%t 2