প্রশ্ন সংশোধন করুন
প্রশ্ন:
If a man swims 4 miters upstream at 1 mph and back downstream to the same point at 4 mph, what is his average speed?
If a man swims 4 miters upstream at 1 mph and back downstream to the same point at 4 mph, what is his average speed?