Frequency 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 midpoint of the seventh class.

• 86

• 91

• 96

• 96.5

• 85.5

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

To construct a histogram, we have to estimate ________ or _______ to label the horizontal axis.

• midpoints - class boundaries

• lower class limits - upper class limits

• frequencies - data entries

• colours - numbers

Observe the histogram and choose the frequency distribution that corresponds to it.

• 
• 

The following data set shows the minutes spent on internet by 50 internet users. Use seven classes to construct a frequency distribution. What's the class width?

• 11

• 12

• 7

• 86

The following data set shows the minutes spent on internet by 50 internet users. Use the class width from the previous question to find the lower class limits if the first lower class limit is the minimum value of the data set.

• 7, 7, 11, 17, 19, 20, ...

• 6.5, 18.5, 30.5, 42.5, 54.5, 66.5, 78.5

• 12.5, 24.5, 36.5, 48.5, 60.5, 72.5

• 7, 19, 31, 43, 55, 67, 79

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.

What is the mode for this data set? Remember the mode is the most common or most frequent data.

• 3

• 4

• 5

• 6

How many cities have temperatures between 70 degrees and 99 degrees?

• 44

• 34

• 26

• 62