Download HM3-n-M3_18-19Nov2015_Stats

Stats
Short Answer
1. A factory manufactures plastic bottles of 4 different sizes, 3 different colors, and 2 different shapes. How
many different combinations are possible?
2. The table shows the heights (in centimeters) of students of class IX.
145
155
155.5
158
160.6
165
170
175
175
175.9
180
8.0
8.6
Find the mean, median, and mode of the heights to the nearest tenth.
3. The table shows the weights (in pounds) of some newborn babies.
4.2
4.5
4.8
5.0
5.5
6.5
6.5
6.5
6.5
7.0
7.4
Find the mean, median, and mode of the weights.
Find the margin of sampling error to the nearest percent.
4. p = 81%, n = 1500
5. p = 48%, n = 500
In a race, Brian Collins has to cross 10 hurdles. The probability that he clears a hurdle is
ability.
. Find the prob-
6. P(knocks down all hurdles)
7. P(clears exactly 2 hurdles)
A dice is rolled 8 times. Find the probability.
8. P(getting even numbers 7 times)
Determine whether the following situation would produce a random sample. Write Yes or No and explain
your answer.
9. surveying people going to a Thai restaurant to find their favorite food
10. asking every tenth student coming out of a college how many times a week they visit a nearby restaurant to
determine how often people in the city visit that restaurant
11. The names of all the students of a class are written on slips of paper. These slips are folded and kept in a bowl.
A student whose eyes are closed draws a handful of slips to find a sample of students in the class.
The marks obtained by students of a class in a test are normally distributed with a mean of 60 marks and a
standard deviation of 5 marks.
12. About what percent of students have scored between 55 and 65 marks?
13. About what percent of students have scored between 60 and 65 marks?
14. About what percent of students have scored less than 45 marks?
15. About what percent of students have scored more than 65 marks?
16. About what percent of students have scored more than 75 marks?
The measurement of the height of 600 students of a college is normally distributed with a mean of 175 centimeters and a standard deviation of 5 centimeters.
17. What percent of students are between 170 cm and 180 cm in height?
18. What percent of students are between 180 cm and 185 cm in height?
19. What percent of students are less than 170 cm in height?
20. What percent of students are taller than 175 cm?
21. What percent of students are taller than 180 cm?
22. Picking the names of the students from an attendance register whose roll numbers are even numbers to select
a sample of students.
23. Calling every person from a particular community in a city to determine which presidential candidate is
favored.
24. Two hundred students at a school basketball game are surveyed to find the students’ favorite sport.
25. Surveying students of an engineering college to determine how often people in that city visit a restaurant near
to that college.
26. Surveying schoolteachers of a city to determine how many people favor the newly framed industry law.
27. Finding the weight of all the newborn babies in El Camino Hospital in California to find the average weight
of a newborn baby in that hospital.
28. Surveying students in the honors Botany classes to determine the average time students in a college spend in
the laboratory each week.
Determine whether the data appears to be positively skewed, negatively skewed, or normally distributed.
29. The table below shows the average employee salary (in thousands) at S&S, Inc for the last five years.
Year
Salary (thousand $)
2000
2001
2002
2003
2004
17
23
30
35
25
30. The table below shows the score of the Jaguar basketball team for the last ten games.
Game
Score
I
47
II
52
III
55
IV
59
V
67
VI
79
VII
76
VIII
68
IX
55
X
55
31. A dice is rolled 8 times. Find the probability P(of exactly 6 occurrences of 3).
32. A coin is tossed 8 times. Find the probability P(of exactly 6 occurrences of tails).
Find the variance and standard deviation of the given set of data to the nearest tenth.
33. {470, 130, 330, 450, 110, 610, 790}
34. {9.5, 13.1, 21.6, 37.9, 30, 44.6, 12, 43.4, 14, 69.2}
Stats
Answer Section
SHORT ANSWER
1. ANS:
24
OBJ: 12-1.1 Solve problems involving independent events.
TOP: Solve problems involving independent events.
2. ANS:
165.0, 165.0, and 175.0
OBJ: 12-6.1 Use measures of central tendency to represent a set of data.
TOP: Use measures of central tendency to represent a set of data.
3. ANS:
6.2, 6.5, and 6.5
OBJ: 12-6.1 Use measures of central tendency to represent a set of data.
TOP: Use measures of central tendency to represent a set of data.
4. ANS:
2%
OBJ: 12-9.2 Find margins of sampling error.
5. ANS:
4%
TOP: Find margins of sampling error.
OBJ: 12-9.2 Find margins of sampling error.
6. ANS:
TOP: Find margins of sampling error.
OBJ: 12-8.2 Find probabilities for binomial experiments.
TOP: Find probabilities for binomial experiments.
7. ANS:
OBJ: 12-8.2 Find probabilities for binomial experiments.
TOP: Find probabilities for binomial experiments.
8. ANS:
OBJ: 12-8.2 Find probabilities for binomial experiments.
TOP: Find probabilities for binomial experiments.
9. ANS:
No, the people surveyed would be probably more likely than others to prefer Thai food.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
10. ANS:
No, the average person of the city might have a different frequency of visiting that restaurant than an average
college student.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
11. ANS:
Yes, all the students have equal chances of being selected.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
12. ANS:
68
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
13. ANS:
34
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
14. ANS:
0.5
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
15. ANS:
16
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
16. ANS:
0.5
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
17. ANS:
68
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
18. ANS:
13.5
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
19. ANS:
16.0
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
20. ANS:
50
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
21. ANS:
16.0
OBJ: 12-7.2 Solve problems involving normally distributed data.
TOP: Solve problems involving normally distributed data.
22. ANS:
No, each student of the class should have an equal chance of being selected.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
23. ANS:
No, there are several communities and cities in a country with different opinions about different candidates.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
24. ANS:
No, students attending this event are more likely to enjoy basketball.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
25. ANS:
No, the average person of the city might have a different frequency of visiting that restaurant than an average
college student.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
26. ANS:
No, schoolteachers cannot represent the general opinion of the society in such surveys.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
27. ANS:
Yes, once the weights of a given number of newborn babies are known, their average weight can be calculated
precisely.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
28. ANS:
No, students in different subjects spend different times in the laboratory.
OBJ: 12-9.1 Determine whether a sample is unbiased.
TOP: Determine whether a sample is unbiased.
29. ANS:
negatively skewed
OBJ: 12-7.1 Determine whether a set of data appears to be normally distributed or skewed.
TOP: Determine whether a set of data appears to be normally distributed or skewed.
30. ANS:
normally distributed
OBJ: 12-7.1 Determine whether a set of data appears to be normally distributed or skewed.
TOP: Determine whether a set of data appears to be normally distributed or skewed.
31. ANS:
0.04%
OBJ: 12-8.1 Use binomial expansions to find probabilities.
TOP: Use binomial expansions to find probabilities.
32. ANS:
10.94%
OBJ: 12-8.1 Use binomial expansions to find probabilities.
TOP: Use binomial expansions to find probabilities.
33. ANS:
Variance = 52,049, Standard deviation = 228.1
OBJ: 12-6.2 Find measures of variation for a set of data.
TOP: Find measures of variation for a set of data.
34. ANS:
Variance = 334.6, Standard deviation = 18.3
OBJ: 12-6.2 Find measures of variation for a set of data.
TOP: Find measures of variation for a set of data.