প্রশ্ন সংশোধন করুন
প্রশ্ন:
Two pipes A and B can fill a tank in 20 and 30 minutes respectively . If both the pipes are used together , then how long will it take to fill the tank ?
Two pipes A and B can fill a tank in 20 and 30 minutes respectively . If both the pipes are used together , then how long will it take to fill the tank ?