The pic on top is the answer to the other question, I couldn’t answer it again so I put it here. Hope this helps
Let's say the distance is "x".
time = distance / rate
time1 = x / 40
time2 = x/80
A) time1 shoud be twice time2 or (time1 / time2) =2
B) time1 -1 = time2
Substituting equation B) into A)
((time1 / (time1 -1) = 2
time1 = 2* time1 -2
time1 = 2 hours time2 = 1 hour
Distance = 80 miles
1st trip time1 = 80/40 = 2 hours
return trip time2 = 80/80 = 1 hour
total trip = 160 miles in 3 hours
average speed = 53.333333 miles per hour
It takes them 208 minutes to paint 20 walls.
