There is an orangutan, a tiger and a lion crossing the river with their son. Three big animals and a small orangutan can row a boat, and they can only cross it twice at a time? B

The gorilla took the little gorilla, put the little gorilla on the shore, then rowed over to pick up either the tiger or the lion, then came back with the little gorilla, then put the little gorilla on the shore and took the rest of the big animals. Finally, when you come back, just pick up the little orangutan. It's simple!