Statistics and Probability Answers

the mean time taken to learn the basics of a software program by all students is 200 minutes with a standard deviation of 20 minutes, the shape of the distribution is unknown. Find the interval that contains the times taken by at least 60% of all students to learn this software program

II. Given sigma μ=45 and σ, = 6, determine and plot the location of the z scores of the following raw scores: 56, 70,82
III. The scores of SLU College Admission Test are normally distributed,with = 80 and = 6. Find the following:
1. What is the percentile rank of 84?
2. What percentageof scores fall between 64 and 90?

Instructions: Show your solutions,
Follow naming guidelines in the syllabus.
I. Using the table, find the following:
1. Mode, Median, Mode
2. Mean Deviation
3. Variance and Standard Deviation

72 44 80 40 44 60 80 43 55 62
73 49 58 48 80 53 52 47 51 80
46 61 41 74 78 56 62 55 75 51
64 40 79 65 76 66 46 60 67 52
76 49 44 47 45 68 57 56 59 68

III. Create a grouped frequency distribution table for the statement below, the table must contain:
1. Class intervals
2. Frequency distribution and percentage
3. Cumulative frequency distribution and percentage
A Psychology 1100 class of BA Procrastination just got their final row score of the course:
49 68 36 52 65 95 97 91 35 56
34 58 42 91 54 59 34 70 93 33
58 32 67 89 81 67 93 43 46 88
50 63 54 68 59 36 66 50 41 78
62 39 82 77 31 35 41 86 52 31

II. Determine which scale of measurement is most valid for the following:
1. University intramurals college ranking
2. Blue corner shirt colors
3. Grade in psychological Statistics Laboratory

QUESTION B1

A study of corruption for a certain geographic region showed an average of 5 corruptions occur per 20,000 people. In a city of 80,000 people, find the probability that at least 3 corruptions occur.

QUESTION B2

(a) A random sample of 300 students from a geographic area indicated that 45 students attended private school. Estimate the true proportion of students attending private schools with 95% confidence.

(b) A survey of 25 individuals who passed the ACCA exam showed that average annual
salary is RM150,000 and standard deviation RM15,000.

(i) Find the degrees of freedom.

(ii) Construct 99% confidence interval for the true average salary.

The probability that a particular type of smoke alarm will function properly and sound an alarm in the presence of smoke is 0.8. You have 2 such alarms in your home and they operate independently. What is the probability that both sound an alarm in the presence of smoke?

Although we don't consciously think of patterns in relationships, we know they exist. Create a new thread in the discussion area for this activity. List a positive, negative, and zero correlation situation. For each correlation, explain your reasoning. Also, give a suggestion as to who might be interested in this trend.

Twenty Companies were asked whether they provide retirement benefits to their employees.
Fourteen of the companies said they do provide retirement benefits to their employees and six
said they do not. Five companies are randomly selected from these 20. Find the probabilities
that:

i. Exactly two of them provide retirement benefits to their employees.
ii. None of them provide retirement benefits to their employees.
iii. At most one of them provides retirement.

b. The number of people arriving for treatment at an emergency room can be modeled by a
Poisson process with a rate parameter of five per hour
i. What is the probability that exactly four arrivals occur during a particular hour?
ii. What is the probability that at least four people arrive during a particular hour?
iii. What is the probability that exactly four arrivals occur during 45 minutes period?