Texas Instruments TI-30X IIS User Manual page 22

What's My Score? — 1-Variable Statistics
2. Now find the average of your friend's scores.
Remember to put 2 as the frequency for 89 and 1
for all others.
3. Who won?
Your friend: 93 (You had 92.6.)
Extension
Present the following problem to students:
Your friend took a test on the day you were absent
and scored 95. What score do you need to get so that
you are the winner?
The score you need: 98
Note: Make sure you exit the
to another problem.
© 1999 T I I
EXAS NSTRUMENTS
mode before going on
STAT
NCORPORATED
³ 1. Press % t " " <
to select
2. Press v and enter the
friend's first score.
X1 = 89
3. Continue entering the
friend's scores and
frequencies, following
steps 3 and 4 on the
previous page.
4. When finished, press
u " to select
average. Write it down.
n v Sx sx
³ 1. Press % t and " "
to
CLRDATA
2. Recalculate your friend's
average, making sure to
include the new score.
3. Use guess and check to
figure out what score you
need to get.
4. To exit
% w <.
TI-30X ÙS: A Guide for Teachers
(Continued)
.
CLRDATA
, the
v
93.0
. Press <.
mode, press
STAT
15