Question 331763
The solution to this problem lies in the equation d=rt
d=distance; da=distance train a travels, db=distance train b travels
r=rate;     ra=80, rb=100
t=time;      ta= time for train a, tb=time for train b
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da=db so ta*ra=tb*rb   train A has a head start by 12 minutes or 80*12/60=16m
da=16+80t=100t=db
16+80t=100t  subtract 80t
16=20t       divide by 20
4/5=t in hours in minutes 4/5*60=48minutes; answer