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In Exercises 4.16–4.26, express your probability answers as a decimal rounded to three places.
4.21 Occupations in Seoul. The population of Seoul was studied in an article by B. Lee and J. McDonald, “Determinants of Commuting Time and Distance for Seoul Residents: The Impact of Family Status on the Commuting of Women” (Urban Studies, Vol. 40, No. 7, pp. 1283–1302). The authors examined the different occupations for males and females in Seoul. The table at the top of the next page is a frequency distribution of occupation type for males taking part in a survey. (Note: M = manufacturing, N = nonmanufacturing.) If one of these males is selected at random, find the probability that his occupation is
- a. service.
- b. administrative.
- c. manufacturing.
- d. not manufacturing.
Occupation | Frequency |
Administrative/M | 2,197 |
Administrative/N | 6,450 |
Technical/M | 2,166 |
Technical/N | 6,677 |
Clerk/M | 1,640 |
Clerk/N | 4,538 |
Production workers/M | 5,721 |
Production workers/N | 10,266 |
Service | 9,274 |
Agriculture | 159 |
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