Answer

Interval - Detected Speed	Frequency	Relative Frequency	Cumulative Relative Frequency
80 - 84	1	2	100
75 - 79	2	4	98
70 - 74	3	6	94
65 - 69	5	10	88
60 - 64	12	24	78
55 - 59	11	22	54
50 - 54	11	22	32
45 - 49	2	4	10
40 - 44	3	6	6

Or

Interval - Detected Speed Frequency Relative Frequency Cumulative Relative Frequency

83 - 87 1 2 100

78 - 82 0 0 98

73 - 77 3 6 98

68 - 72 7 14 92

63 - 67 0 0 78

58 - 62 17 34 78

53 - 57 12 24 44

48 - 52 5 10 20

43 - 47 3 6 10

38 - 42 2 4 4

Note that by simply changing the selected intervals, the frequency tables represent the data differently. Each will be graphed below. Note the differences.

Same Data - Different Intervals

Histogram Histogram

Frequency Polygon Frequency Polygon

There is an error in the graph! Can you spot it?

Ogive Ogive

Back to Practice Problems: Tables and Graphs

Histogram	Histogram

Frequency Polygon	Frequency Polygon
	There is an error in the graph! Can you spot it?
Ogive	Ogive