maria ran the obstacle course each day during her gym class and recorded the follwing monday 51.6sec tuesday 58.6sec wednesday 48.3sec thurday 52.7sec on friday she ran the obstacle course again the mean (average) time for all five days is 52 seconds what was maria time friday?

2 answers

Add each day's time. Divide the total by 4. That will give the average for these four days.
Or add four days time and include x. then multiply 52 by 5 after that solve for x
day time 1+2+3+4+x=52*5