Texas Instruments TI-73 Teachers Manual page 69

64
Using the TI-73: A Guide for Teachers
Demonstrate to students how to measure a foot, from
heel to toe, so that everyone is measuring the same.
Ask:
What unit should we use to measure? (inches)
What if there are parts of an inch left? Will we record
it as a decimal or fraction? (Fraction would probably
be easiest for this part.)
Do we need to measure both feet or just one foot?
Should we measure with the shoe on or off?
Activity
Have students perform the steps unless otherwise
indicated.
1. Have each student measure 20 people, or the number
of people that the class decides to measure. Students
need to decide how many adults and how many
children they will measure. They may use the activity
sheet provided to organize their data.
2. Once students have collected data, ask:
What is an average?
How will we find out if the average foot size in our
survey is 12 inches, or a foot? (Add them all together
and divide by the number of feet measured.)
How will we add the fractional parts? (If you wish,
you can convert them to decimals using the TI-73. See
the example in the next step.)
3. Find the averages from the data.
a. Go to the Home screen.
- l
b. Convert fractions to decimals by using the > key
on the TI-73.
Example To convert 12¼ inches to a decimal,
c. From the Home screen, find the mean using
traditional methods.
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EXAS NSTRUMENTS
enter Y Z < Y = Q > b.
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