SECTION 10.1 Goodness-of-Fit Test 533 9. Ordering Pizza A research firm claims that the distribution of the days of the week that people are most likely to order pizza (including delivery, takeout, and sitting at restaurants) is different from the distribution shown in the figure. You randomly select 500 people and record which day of the week each is most likely to order pizza. The table shows the results. At a = 0.01, test the research firm’s claim. (Adapted from Womply) Pizza Day Day of the week Americans are most likely to order pizza. 13% 21% 19% 14% 10% 11% 12% Wednesday Friday Saturday Sunday Tuesday Thursday Monday Survey results Day Frequency, f Sunday 54 Monday 32 Tuesday 44 Wednesday 75 Thursday 59 Friday 114 Saturday 122 10. Ways to Pay A financial analyst claims that the distribution of people’s preferences on how to pay for goods is different from the distribution shown in the figure. You randomly select 600 people and record their preferences on how to pay for goods. The table shows the results. At a = 0.01, test the financial analyst’s claim. (Adapted from Travis Credit Union ) Preferred Way to Pay Cash 29% Debit or credit 59% Check 5% Digital wallet/other 7% Survey results Response Frequency, f Cash 194 Debit or credit 338 Check 21 Digital wallet/other 47 11. Homicides by County A researcher claims that the number of homicide crimes in California by county is uniformly distributed. To test this claim, you randomly select 1000 homicides from a recent year and record the county in which each happened. The table shows the results. At a = 0.01, test the researcher’s claim. (Adapted from California Department of Justice) County Frequency, f Alameda 58 Contra Costa 44 Fresno 53 Kern 79 Los Angeles 151 Monterey 34 Orange 40 Riverside 86 County Frequency, f Sacramento 62 San Bernardino 98 San Diego 69 San Francisco 38 San Joaquin 55 Santa Clara 49 Stanislaus 45 Tulare 39
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