Question

The ‘moving walkway’ is a 300-foot long walkway consisting of a conveyor belt that moves continuously at 3 feet per second. When Bill steps on the walkway, a group of people that are also on the walkway stands 120 feet in front of him. He walks toward the group at a rate of 3 feet per second. Once Bill reaches the group of people, he stops walking and stands with them until the walkway ends. What is Bill’s average rate of movement for his trip along the moving walkway?A. 2 feet per secondB. 2.5 feet per secondC. 3 feet per secondD. 4 feet per secondE. 5 feet per second

Answer 1

C. 3 feet per second

Explanation:

Step 1: total time taken to complete the walkway journey

Total time taken = 300ft/3ft/sec = 100sec

Step 2: remaining distance to be covered by the group of people standing 120ft in front of Bill is:

300ft-120ft = 180ft

Step 3: time taken for the to cover the remaining 180ft distance is;

180ft/3ft/sec = 60sec

Step 4: time required for Bill to catch up with the people will be

100sec - 60sec= 40sec

Step 5: Hence, Bill's average rate of movement = 120ft/40sec = 3 feet per second

OR

300ft/(60sec + 40sec) = 3 feet per second