Question 348415
D=RT
D=60T FOR THE TRUCK.
D=71(T-8/60)
60T=71(T-4/30) 
60T=71T-284/30
60T-71T=-9.467
-11T=-9.467
T=-9.467/-11
T=.86 HOURS OR 51.64 MINUTES TO PASS THE TRUCK.
PROOF:
60*.86=71(.86-8/60
51.6=71(.86-.1333)
51.6=71*.627
51.6=51.6