Question 29831
First,find out how long it takes Jeff and Carla to drive from SLO to Lake Tahoe using: distance (d) = rate (r) X time (t).

{{{d = rt}}} Rewrite as:
{{{t = d/r}}}

For Jeff:

{{{t = 425/55}}}
{{{t = 7.73}}}hrs.

For Carla:

{{{t = 425/65}}}
{{{t = 6.54}}}hrs.

Next, add the driving times to the starting times to see who arrives first.
It simplifies things a bit if you use the 24-hour clock.
11:00 AM = 11.00 hours
1:00 PM = 13.00 hours.

For Jeff, arrival time is: 
11.00 + 7.73 = 18.73 hours. This is 6:44 PM

For Carla, arrival time is:
13.00 + 6.54 = 19.54 hours. This is 7:32 PM

Jeff arrives in Lake Tahoe first.