Question 1116210
x + x+6 = 171
2x+6 = 171
2x = 165
x = 82.5
82.5/1.5 = 55 mph this is the speed of the other car.
One car is traveling 6mph faster than the other car: 55 + 6 = 61 mph
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So there you have it:
One car: 61mph
The other: 55mph