Answer: 1.8 mi.
Explanation:
Formula for distance, rate, time
d = rt >I think of dirt
x = r, rate
Trip up:
r= 45 min = .75 hr >convert by dividing by 60
d = x(.75) This is in
d = x
x = d/.75
Trip down:
r= 20 min = .333 hr
d = (x+3)(.333) >distribute
d = .333x + 1
Substitute trip up into trip down equation and solve for d
d = .333(d/.75) +1
d = .444d +1 >subtract .444d from both sides
.555d = 1 >divide .555 to both sides
d = 1.8 mi