A large tanker can be filled by two pipes A and B in 60 minutes and 40 minutes, respectively. How many minutes will it take to fill the empty tanker if only B is used in the first-half of the time and A and B are both used in the second-half of the time?

• ক 30 minutes ✅ সঠিক উত্তর
• খ 27.5 minutes
• গ 20 minutes
• ঘ 16 minutes