For her exercise today, keiko plans to both run and swim. let r be the number of laps she runs and let s be the number of laps she swims. each lap she runs takes her 5 minutes, and each lap she swims takes her 3 minutes. she wants to exercise for at least 30 minutes today. using the values and variables given, write an inequality describing this.

5r + 3s ≥ 30

Step-by-step explanation:

We know Keiko wants to do exercise at least 30 minutes a day, and she wants ideally to mix up the activities, by combining running and swimming into her schedule.

Since each lap she runs takes 5 minutes and each lap she swims takes 3 minutes, these will be the left side of the inequality:

5r + 3s

She wants to exercise at least 30 minutes a day, so...

5r + 3s ≥ 30

she could do 3 laps of running and 5 laps of swimming for example.

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m