How do you figure out where to begin when you set up simple liner equations for the question below?

Background:

The 2010 National Hospital Ambulatory Medical Care Survey (NHAMCS) is a national (United States) sample survey of visits to hospital outpatient and emergency departments. This survey was conducted by the National Center for Health Statistics. In this exercise, simple linear regression will be used to examine factors associated with patient waiting time (in minutes) of persons admitted to the Emergency Departments (EDs) of participating hospitals in 2010. The average waiting time reported by the over 27,000 survey participants is 56.3 minutes (s= 78.7 minutes, with a range of 0 to 1,335 minutes).

To start, a simple linear regression was performed to relate average ED waiting times to subject's sex, with x1 coded as 1 for male and 0 for female.

" = 57.4 + 2.5-, and the estimated standard error of the slope for sex is 0.95. The R2 for this regression is < .01.

Based on these results:

What is the mean waiting for females in the sample?