1. A random sample of 12 employees in a large manufacturing plant found the following figures for number of hours of overtime worked in the last month:

2 5 4 10 3 3 10 16 15 9 14 11 Find range, mean, median, mode, and standard deviation of the data.

2. The grades on a math midterm are normally distributed with= 75 and= 2.4. Mary scored 78 on the midterm. The grades on the final exam are normally distributed with= 71 and= 1.8. Mary scored 75 on the final exam. Is her final grade better (with respect to the average) than her midterm grade? Why?

3. Employees were asked to indicate their level of satisfaction with their current medical insurance. Responses from a random sample of employees follow:

• Very satisfied 20
• Moderately satisfied 54
• No opinion 3
• Moderately dissatisfied 10
• Very dissatisfied 2

1. (a) Is it a quantitative variable or a categorical variable?
2. (b) Construct the relative frequency distribution and draw its histogram.
3. (c) What is the mode? (d) What is the median?
4. (e) Can you compute the mean?