Andrea has 1 hour to spend training for an upcoming race. She completes her training by running full speed the distance of the race and walking back the same distance to cool down. If she runs at a speed of 9mph and walks back at a speed of 3mph, how long should she plan to spend walking back?

  3/4 hour

Step-by-step explanation:

The ratio of speeds going : coming is 9 : 3 = 3 : 1. The ratio of times will be the inverse of this: 1 : 3.

The time spent walking back is 3/(1+3) = 3/4 of the total, or 3/4 hour.

Andrea should plan on walking back for 3/4 hour.

step-by-step explanation:

i think its about 8