Give elaborate explanation


I could not understand the solution.
Please share the full explanation.


Let’s say she has to drive for ‘X’ minutes from home to reach station. So on a typical day she’ll start at from home exactly at 6 - X PM, reach station at 6PM, reach home back at 6 + X PM. Total time taken for car trip is 2X minutes. But on this particular day, since she didn’t have to go all the way to the station to pick him up, they reached home at 6+X-20 PM. So total time taken for car trip is 2X-20. So one way she drove for X-10 minutes. Since she started at 6-X PM and drove for X-10 minutes, they met exactly at 6-X+X-10 => 6 -10min => 5:50PM. Since he started walking at 5PM, he walked for 50minutes.