1. The following poll shows employees engagement with their work. The study also shows that having more engaged workers leads to increased innovation, productivity and profitability, as well as reduced employee turnover.
Country
|
Engagement
|
USA
|
Germany
|
Total
|
|
Engaged
|
550
|
246
|
796
|
|
Not engaged
|
1 345
|
1 649
|
2 994
|
|
Total
|
1 895
|
1 895
|
3 790
|
If an employee is selected at random, what is the probability that he or she
a) is engaged with his or her workplace
b) is a US worker
c) is engaged with his or her workplace or is a US worker
d) explain the difference in the results in (b) and (c)
2. From the last year's data was found that the pizza restaurant filled the orders approximately 91% correctly. What is the probability that
a) All five orders will be filled correctly
b) None of the five will be filled correctly
c) At least four of the five will be filled correctly
3. For a survey, final exam grades of 100 students are gathered. The mean grade was 28 on a 40 based scale with a standard deviation of 4 Assume that the grades of students are approximately normally distributed. For a randomly selected student what is the probability that he or she scores
a) Below 20?
b) Above 35?
c) Between 25 -35?
4. 10 liter of petrol is put in each of the 30 test autos and the resulting figures are tabulated as follows: mean X = 120 km, s = 15 km. Determine a 99% confidence interval estimate of the mean mileage.