Five bells first begin to toll together and then at intervals of 5, 10, 15, 20 and 25 seconds respectively. After what interval of time will they toll again together?
Q1. Five bells first begin to toll together and then at intervals of 5, 10, 15, 20 and 25 seconds respectively. After what interval of time will they toll again together?
Answer: 5 min
Explanation: LCM(5, 10, 15, 20, 25) = 300 seconds = 5 minutes, so all five bells toll together every 5 minutes.