A small delivery company in Rio de Janeiro has 85 trucks that service various stops seven days a week. The trucks are typically in service from 9am until 5pm, daily. It is costly to the company to have drivers work daily shifts longer than eight hours because overtime would have to be paid. The company wants to avoid overtime payments, but, given trac in Rio, this is not always possible. A regression was conducted to analyze time needed to complete the trucks' daily routes. The regression output is reported in the worksheetRio Trucksof the Excel workbookFinalExam Outputs.

The variables in the regression model are the following.

?Hours:the number of hours needed to complete truck's daily schedule;?Stops:the number of delivery stops in the truck's daily schedule;

?Weekend:dummy variable for weekend days

-Weekend= 1 for Saturday and Sunday

-Weekend= 0 for weekdays (Monday, Tuesday, Wednesday, Thursday, and Friday)

If thirty stops were scheduled for each of the 85 trucks on a weekday, what is the probability that at least 65 trucks would be able to complete their route within the regular eight hour window?

Dependent Variable: Hours Independent Variables: Stops, Weekend Regression Statistics R Square Adj.RSqr Std.Err.Reg. # Cases # Missing t(2.5%, 123) 0.234 0.221 1.141 126 1.979 Summary Table Variable Coeff Std.Err. t-Stat. P-value Intercept 4.112 0.619 6.640 0.000 Stops 0.091 0.017 5.458 0.000 Weekend -0.687 0.225 -3.051 0.003 Forecasted : Hours Stops Weekend Forecast StErrFst Fost# 1 30 O 6.846 1.152 Fest# 2 30 6.158 1.163 - - Fost# 3 31 6.249 1.161 Fost# 4 32 6.340 1. 160 Fest# 5 33 6.431 1.159 Fost# 6 34 6.523 1.158 Fost# 7 35 6.614 1.157 Fost# 8 36 6.705 1.157 Fost# 9 37 6.796 1.157 Fest# 10 38 6.887 1.157 Fost# 11 39 6.978 1.157 Fost# 12 40 - 7.069 1.158