# MS 150 Statistics t01 3.4 speed trap • Name:

Using a Bushnell radar speed gun, the speed of vehicles on two stretches of road were measured on Saturday 23 January 2011 at around 9:30 in the morning.

Causeway

v (kph)
40
55
39
68
44
1. __________ Find the sample size n.
2. __________ Find the mode.
3. __________ Find the median.
4. __________ Find the sample mean x.
5. __________ Find the sample st. dev. sx.
6. __________ Find the sample CV.

Hospital

v (kph)
23
34
41
29
38
1. __________ Find the sample size n.
2. __________ Find the mode.
3. __________ Find the median.
4. __________ Find the sample mean x.
5. __________ Find the sample st. dev. sx.
6. __________ Find the sample CV.
v (kph)
23
29
34
38
39
40
41
44
55
68

Use the table on the right for this section of the test.

1. __________ What is the level of measurement for the data?
2. __________ Find the minimum.
3. __________ Find the maximum.
4. __________ Find the range.
5. __________ Find the midrange.
6. __________ If this data is to be divided into five classes, what is the width of a single class?
7. Determine the frequency and calculate the relative frequency using five classes. Record your results in the table provided.
Class upper limitsFrequency FRelative Frequency p(x)
Sums:
8. Sketch a frequency histogram of the data, labeling your horizontal axis and vertical axis as appropriate.
9. _______________ What is the shape of the histogram?
10. __________ Using only the Causeway average and standard deviation, calculate the z-score for a car that was measured at 78 kph.
11. __________ Using only the Causeway average and standard deviation, is 78 kph a statistically ordinary or unusual speed based on the z-score?