Answer:
Explanation:
The difference in distance traveled is 40 miles, so each train must have traveled 2 hours.
Train A speed = (320 mi)/(2 h) = 160 mi/h
Train B speed = (280 mi)/(2 h) = 140 mi/h
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The difference in speed means Train A gains on Train B by 20 miles each hour. After 2 hours, it will have gone 40 miles farther.