Raymond B. answered 01/09/26
Math, microeconomics or criminal justice
1 hr 20 min trip
one 3 mph faster
slower one went x mph for t hours x=20 mph t=8/9 of an hour = 160/3 = 53 minutes 20 seconds
faster one went x+3 mph for 4/3-t hours x+3 = 23 mph, 4/3-t = 4/9 of an hour = 80/3= 26 min 40 sec
distance = 28 miles = d = rt = (x)(t) + (x+3)(4/3 -t)
28 = xt + -xt -3t+ 4 + 4x/3
24= 4x/3 -3t
72 = 4x -9t
average speed = 28/4/3 =21 mph
23 for fast guy 20 for slower
4(20) - 9t = 72
9t = 80-72=8
t =8/9
T=4/9
20x8/9 + 23x4/9 = (160+92)/9 = 252/9 =28 miles