Problem of the Week - Algebra and Up - Nov. 8, 2020 to Nov. 14, 2020

Algebra and Up: 

Question: Jack is running through a maze with a total of 6,000 yards of passages. Jack runs through 40% of the passages, and he retraces 25% of his progress through the maze. If Jack runs for 10 minutes before he stops, then what was the average speed at which he ran through the maze? Give your answer in yards per second. 

Answer:  5 yards per second

Solution:  Jack runs through 40% of 6,000 = 2,400 yards of the maze, but since 25% of those 2,400 yards are retraced, he runs 2,400 × 1.25 = 3,000 yards. So, he runs 3,000 yards in 10 minutes, which is 300 yards per minute and 5 yards per second.