## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$75$ miles per hour
At 12 noon, the train was 100 miles from Chicago By 2 P.M., the train was 250 miles from Chicago The increase in distance from Chicago is: $=250-100=150$ miles The elapsed time from 12 noon to 2 p.m. is 2 hours. Thus, the average rate is: $=\dfrac{150\text{ miles}}{2 \text{ hours}}=75$ miles per hour