Transcript Lesson 3

Module E
Statistics with
TI-Nspire™ Technology
Module E
Statistics with
TI-Nspire™ Technology
Lesson 3: Exercises
In the previous lesson you learned:
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How to generate a random sample.
To calculate statistics of a sample.
To draw a histogram and change the bin settings.
To draw a function above the histogram and compare the histogram with
the distribution of the population.
 To draw a box-plot and a dot-plot.
 To use the dynamic link between the plots and the data to explain the
difference between the mean and the median.
3 | Lesson E.3
TI-Nspire™ Technology
In this lesson you will:
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Use the TI-Nspire software, installed on your computer to do some
exercises.
Examine the relationship between the speed of a car and its stopping
distance.
Check a statement about probability density functions.
Practice the things you learned in the previous lessons.
4 | Lesson E.3
Exercise 1
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Many drivers drive in a false belief that if the car in front suddenly starts
braking, they would react and brake and end up stopped the same distance
apart.
The total stopping distance of a vehicle is made up of 2 components:
• Human Reaction Time (reaction distance)
• Vehicle Braking Capability (braking distance)
The human reaction time is how long the body takes to move the foot from
accelerator to the brake pedal. This reaction time can vary from ¼ - ¾ of a
second. This is a human factor and as such can be affected by tiredness,
alcohol and concentration levels.
The vehicle braking capability determines how long it takes to stop the car,
once the brake pedal is pushed.
5 | Lesson E.3
Exercise 1
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For several speeds you can see the reaction distance and the braking
distance of a car in good weather conditions.
Speed
(km/h)
Reaction distance
(m)
Braking distance
(m)
30
9
5
50
14
13
70
19
25
90
25
41
120
33
72
140
39
98
Question: Examine the relationship between the reaction distance
and the speed, and between the braking distance and the speed.
6 | Lesson E.3
Exercise 2
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The larger the sample the better the sample distribution looks like
the distribution of the population.
QUESTION:
Use TI-Nspire Technology to illustrate
this statement for a normal population
of lengths of 17 years old boys with
mean 178 cm and standard deviation 7
cm. Use a sample of 10, 100, 500 and
1000 values.
7 | Lesson E.3
Congratulations!
You have just finished lesson E.3!
8 | Lesson E.3