5r + 3s ≥ 30
Explanations:The number of Laps he runs = r
The number of laps he swims = s
Each lap he runs takes 5 minutes
The total time he uses to run = 5r
Each lap he swims takes 3 minutes
The total time he uses to swim = 3s
The total time he uses to do both running and swimming = 5r + 3s
He wants to exercise for more than 30 minutes
The inequality describing this illustration is:
5r + 3s ≥ 30
