You jog at a speed of 6 miles per hour for 20 minutes and yo

You jog at a speed of 6 miles per hour for 20 minutes, and you
walk at a speed of 4 miles per hour for t minutes. If your combined
jogging and walking distance is 3 miles, for how long did you walk?

Solution

Be sure to convert from minutes to hours
20 minutes =1/3 hour
r*t=d
6*1/3=2
3miles total -2 miles jogged =1 mile walked
r*t=d
4*t=1
t=1/4 hour or 15 minutes walked