Frequency and Histograms

Observe the frequency distribution:

Estimate the relative frequency of the fourth class.

• 69

• 5.3

• 0.189 or 18.9%

• 0.54 or 54%

Observe the frequency distribution:

Estimate the class boundaries.

• 20, 31, 42, 53, 64, 75, 86, 96

• 20, 31, 42, 53, 64, 75, 86

• 19.5, 30.5, 41.5, 52.5, 63.5, 74.5, 85.5, 96.5

• 30, 41, 52, 63, 74, 85, 96

Which of the following statements corresponds to a frequency distribution?

• a table that shows the number of times a data entry appears in a data set.

• a data set that shows the number of data entries that appear in a time.

• a conclusion drawn from a sample.

• the boundaries between two consecutive bars.

How many classes are there?

• 6

• 30

• 1-5

• 1-30

What is the midpoint of the first class?

• 4

• 5

• 1

• 3

What is the class boundary between the second and third class?

• 10

• 11

• 10.5

• 6

What is the relative frequency of the first class?

• 0.139 or 13.9%

• 0.5 or 5%

• 1-5

• 5

What is the cumulative frequency of the third class?

• f_{1 +} f₂ + f₃ = 5 + 8 + 6 = 19

• f_{1 +} f₂ + f₃ = 5 + 6 + 10 = 21

• f_{1 +} f₂ + f₃ = 1 + 6 + 11 = 18

Observe the frequency distribution:

Estimate the class width.

• 11

• 10

• 25

• 19.5

Estimate the first class boundary (the "lower" class boundary of the first class).

• 19.5

• 20

• 25

• 20.5