© 1999 T
EXAS
I
NSTRUMENTS
I
NCORPORATED
TI-30X
Ù
S: A Guide for Teachers
17
Heart Rates — 1-Variable Statistics
Overview
Students use the statistics functions of the
TI-30X
Ù
S calculator to investigate the effect of
exercise on heart rate.
Math Concepts
• mean,
minimum,
maximum, and
range
Materials
• TI-30X
Ù
S
• stopwatch or
a watch with
a second hand
• student activity
Introduction
Students may be placed in smaller groups for this
activity to minimize the amount of data to be
entered. Ask students:
•
What do you think the average heart rate is for
someone your age?
•
What about after exercising?
Activity
Have students complete the following investigation
to check their estimations.
1. Have students check their resting heart rates by
timing their pulse for 1 minute. (You could have
them time for 10 seconds and then multiply by 6,
but this could be the quietest minute of your day!)
2. Collect data on the chart. Enter each students
heart rate and a mark in the frequency column.
As other students have the same heart rate, add
another tally mark in the frequency column.
3. Enter the heart rate data into the TI-30X
Ù
S.
a. Enter the first heart rate on the chart as the
first
X
value, and the number of tallies for
that heart rate as the frequency.
b. You must press
$
between entries. For
example, enter the first heart rate, and then
press
$
. Enter the first frequency, and then
press
$
.
For example, assume a class of 22 students:
Rate
Students
Rate
Students
60
3
63
3
61
5
64
1
62
6
65
4
³
1. Press
%
t
<
.
2. Press
v
to enter the
heart rates and
frequencies.
X1=
3. Enter first heart rate and
press
$
.
FRQ=
4. Continue entering until
you have entered all the
heart rates and
frequencies.
