Homework - Frequency Distributions

DIRECTIONS: When computation is required, show all work neatly. For example, if you need to calculate a range, you must show those calculations.

When asked to create frequency distributions in this assignment, list each of the following (in its own column):

• stated or apparent limits (only needed for grouped data)
• midpoints (only needed for grouped data)
• real or exact limits
• frequencies (f)
• proportions (p)
• percents (%)
• cumulative frequencies (Cf)
• cumulative proportions (Cp)
• cumulative percents (C%)

• remember the convention of keeping decimal usage consistent within a column.
• make sure to attach Minitab output & label appropriate/important data. In this case, you should be labeling the fact that, while Minitab's presentation of the distribution is upside down, the columns it computes should give the same results that you calculated by hand.

Problems

1. Manually create an ungrouped frequency distribution and then use Minitab to create it. The data represent the average number hours of sleep per night for a bunch of teenagers (30 points; 25 for hand calculations & 5 for MTB).
5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 9, 10, 10, 10, 10, 11, 11.

2. Manually create a grouped frequency distribution and then use Minitab to create it. The data represent hypothetical scores on an exam (30 points; 25 for hand calculations & 5 for MTB).
63 88 79 92 86 87 83 78 41 67
68 76 46 81 92 77 84 76 70 66
77 75 98 81 82 81 87 78 80 60
94 79 52 82 77 61 77 70 74 61
3. Manually create a grouped frequency distribution and then use Minitab to create it. The data represent the number of hours of TV watching per week for 40 students (30 points; 25 for hand calculations & 5 for MTB).
6  8  7  9 18  8  8  7  4  6
6 10 14  8  9 25 18  7 17 16
7 27 19 30  8 20 11  7  8 12
9 17 15 18 17 35  7  7  7 16

Multiple Choice (10 points)

1. Minitab is MOST like what other mainstream software application?
a. Wordprocessor
c. Database
d. Browser
e. Messaging

2. If a set of frequencies that are converted to percentages are summed, the total should equal
a. ≈1
b. ≈100
c. N
d. cannot specify beforehand