Question 28961
City Data:
 rate=x;time=1 hr.; distance =(rate)(time)=x miles
Hyway Ddata:
 rate=2x; time=4 hrs.; distance = (rate)(time)=8x
EQUATION:
distance + distance = 387 miles
x+8x=387
9x=387
x=43 mph of city driving; will cover 43 miles in one hour
2x=86 mph of hyway driving; will cover 4(86)=344 miles in four hours
Cheers
stan H.