Tap A fills 5 h, B fills 10 h. Both open, fill time?
Q1. Tap A fills 5 h, B fills 10 h. Both open, fill time?
Answer: 3.33 h
Explanation: Combined rate 1/5 plus 1/10 equals 3/10 so 3.33 hours. Work each step carefully; ISSB math rewards accuracy under time pressure.