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 frequencies, which are the proportion of responses in each category. For example, the relative frequency for “none” of 0.17 = 85/500.

Table 1. Frequency Table for the iMac Data.

Pie Charts

The pie chart in Figure 1 shows the results of the iMac study. In a pie chart, each category is represented by a slice of the pie. The area of the slice is proportional to the percentage of responses in the category. This is simply the relative frequency multiplied by 100. Although most iMac purchasers were Macintosh owners, Apple was encouraged by the 12% of purchasers who were former Windows users, and by the 17% of purchasers who were buying a computer for the first time.

Figure 1. Pie chart of iMac purchases illustrating frequencies of previous computer ownership. 67