Name: 

Determine the median of the following test scores.
History Test 1 Scores (out of 100)
90      84      77      66
89      84      77      65
86      82      75      65
86      81      72      61
84      79      70      56

A company measured the lifespan of a random sample of 30 light bulbs. Times are in hours.
      985      1001      1024      1087      952
      910      938      931      1074      1081
      1078      1080      982      1108      1022
      937      922      1017      1093      1115
      880      1048      917      1086      935
      936      986      1038      954      966

What value goes in the fourth row of this frequency table?

Lifespan (hours)	Frequency
850–899	1
900–949	8
950–999	6
1000–1049
1050–1099	7
1100–1149	2

Environment Canada recorded the amount of rain (in millimetres) in Jasper, AL for two months.
0      0      0      3.8      9.0      0      0
0      0      0      0      0      0      7.4
0.2      0      1.2      0      2.2      0
0      0      6.4      2.0      4.6      0
0      1.0      0      1.2      0      0
0      0.4      0      3.4      0      1.6
0      0      0      0      1.2      5.0
0      1.4      0      0      0.2      7.2
1.4      4.6      0      5.8      1.2      0
0      0      0      3.2      0.6      0

What value goes in the first row of this frequency table?

Precipitation (mm)	Frequency
0–1.9
2.0–3.9	5
4.0–5.9	4
6.0–7.9	3
8.0–9.9	1

At the end of a bowling tournament, three friends analyzed their scores.
Erinn’s mean bowling score is 92 with a standard deviation of 14.
Declan’s mean bowling score is 130 with a standard deviation of 18.
Matt’s mean bowling score is 116 with a standard deviation of 22.

Who is the more consistent bowler?

Environment Canada compiled data on the number of lightning strikes per square kilometre in Alberta and British Columbia towns from 1999 to 2008.
0.42      0.04      0.81      0.40      0.03      0.74
0.28      0.03      0.70      0.23      0.03      0.66
0.13      0.02      0.61      0.12      0.01      0.58
0.10      0.00      0.49      0.07      1.08      0.43
0.05      0.91      0.42      0.04      0.88

Determine the mean, to two decimal places.

A company measured the lifespan of a random sample of 30 light bulbs. Times are in hours.
      985      1001      1024      1087      952
      910      938      931      1074      1081
      1078      1080      982      1108      1022
      937      922      1017      1093      1115
      880      1048      917      1086      935
      936      986      1038      954      966

Determine the mean, to one decimal place.

A set of data is normally distributed. What percent of the data is within two standard deviation of the mean?

A set of data is normally distributed. What percent of the data is greater than the mean?

The ages of participants in a bonspiel are normally distributed, with a mean of 40 and a standard deviation of 10 years. What percent of the curlers are older than 60?

A teacher is analyzing the class results for a physics test. The marks are normally distributed with a mean (µ) of 76 and a standard deviation (s) of 4.
Determine Guy’s mark if he scored µ + 2s.

Determine the z-score for the given value.
µ = 52, s = 6, x = 64

A poll was conducted about an upcoming election. The result that 44% of people intend to vote for one of the candidates is considered accurate within ±2.7 percent points, 19 times out of 20.
State the confidence interval.

The results of a survey have a confidence interval of 28% to 34%, 19 times out of 20.
Determine the margin of error.

In a recent survey of high school students, 72% of those surveyed agreed that school should start half an hour later. The survey is considered accurate to within 3.5 percent points, 19 times out of 20.
If a high school has 1200 students, state the range of the number of students who would agree with the survey.

In a recent survey of high school students, one third of those surveyed said they would vote for Melissa as student council treasurer. The survey is considered accurate to within 5 percent points, 19 times out of 20.
If a high school has 1200 students, state the range of the number of votes Melissa should expect.

An apple orchard has 32 trees with these heights, given in inches.
      116      90      91      99      114      110      124      102
      82      89      104      102      95      105      118      118
      110      97      92      93      91      116      101      101
      116      86      101      83      117      93      132      104

Complete the frequency table.

Height (in.)	Frequency
80–89
90–99
100–109
110–119
120–129
130–139

Environment Canada compiled data on the number of lightning strikes per square kilometre in Quebec towns from 1999 to 2008.
1.41      0.96      0.48      0.30      0.03
1.32      0.90      0.47      0.19      0.02
1.25      0.71      0.29      0.18      0.02
1.11      0.57      0.49      0.15      0.00
1.02      0.41      0.10      0.11     
1.01      0.17      0.49      0.08     
0.98      0.99      0.32      0.04     

Determine the standard deviation, to two decimal places.

The results of a survey have a confidence interval of 44.8% to 51.6%, 19 times out of 20.
Determine the margin of error.

Billy has 15 min to get to his after-school job. Despite his best efforts, he is frequently late. His employer says that unless he arrives to work on time consistently, he will lose his job. He has recorded his travel times (in minutes) for the last two weeks: 11, 13, 19, 18, 13, 15, 17, 17, 20, 16. Over the next two weeks, he continues to record his travel times: 16, 15, 13, 18, 13, 26, 14, 16, 14, 16.
Do you think Billy will lose his job? Use statistics to justify your answer.

The following table shows Ryan Getzlaf’s regular season statistics while playing in the Western Hockey League (WHL), American Hockey League (AHL), and the NHL from 2001 to 2010.

Season	Games Played	Goals	Assists	Points
2001–2002	63	9	9	18
2002–2003	70	29	39	68
2003–2004	49	28	47	75
2004–2005	51	29	25	54
2005–2006	17	8	25	33
2006–2007	82	25	33	58
2007–2008	77	24	58	82
2008–2009	81	25	66	91
2009–2010	66	19	50	69

In the 2005–2006 season, Ryan played only 17 games. As a result, he had fewer opportunities to score points. Determine the mean and standard deviation for his points, with and without the 2005–2006 season. How do the results compare?

An advertisement for a new toothpaste states that 80% of users reported better dental check-ups. The results of the poll are accurate within 4 percent points, 9 times out of 10.
a) State the confidence level.
b) Determine the confidence interval.
c) In a focus group of 50 students, four said they already used this toothpaste and another five did not want to try it. Determine the range of the mean number of the remaining students who could expect better dental check-ups.