A train covers 300 miles in 3 hours. What is its average speed in mph?

• A. 150
• B. 100
• C. 90
• D. 200

Answer: (B)

Average speed tells you how far you go on each hour, so you divide total distance by total time. The train travels 300 miles in 3 hours, so 300 ÷ 3 = 100. That means the average speed is 100 miles per hour.

Think about the other options by how long they would take to cover 300 miles. At a higher speed, the trip finishes sooner (for example, 150 mph would take about 2 hours; 200 mph would take about 1.5 hours). At a lower speed, it takes longer (90 mph would be about 3.33 hours). Since the given trip is 3 hours, the speed that fits is 100 mph.