Lynda previous best time was 52.9 second.
Given that, Lynda runs the 400 meter for her school's track team.
She beat her best time by 3.6 seconds in the meet today with a time of 49.3 seconds.
It means that, previous best time of Lynda was 3.6 second more than as compared to todays time.
So that,
Previous best time is, [tex]=49.3+3.6=52.9seconds[/tex]
Learn more about the time here:
https://brainly.com/question/26292783