Question. Rhonda, Sally, and Diane are members of their school's track team. The three of them run the 600-meter relay race together. Rhonda runs the first 200 meters of the race, Sally runs the second 200 meters of the race, and Diane runs the final 200 meters of the race. Rhonda can run 200 meters in 24 seconds. Sally takes two seconds longer to run the same distance, while Diane can run 200 meters three seconds faster than Rhonda. How many seconds does it take for the three of them to run the 600-meter relay race?
Answer. 71
What step-by-step reasoning justifies that answer?
Reasoning: Sally takes 24 + 2 = 26 seconds. Diane takes 24 - 3 = 21 seconds. Thus, the three take 24 + 26 + 21 = 71 seconds to run the 600 - meter relay race.