Parents with two children - a son and a daughter - came to a wide river. There was no bridge there. The only way to get to the other side was to ask a fisherman if he could lend them his boat. However, the boat could carry only one adult or two children.
How does the family get to the other side and return the boat to the fisherman?



This situation can be solved as follows 

first the two will go to other side of river by boats and one child will land on bank of river and other child come back with boat .Now father will seat in boat and cross the river and other child again take the boat back and now both children again cross the rive and come to father and now one child take back boat and this time mother will cross the river .now child wit mother and father take back boat and now again two children come back in boat to parents and then one child again take back boat  and  this time fisherman takes the boat to other shore now child at this shore take  boat back and both children sit in boat and come back to parents and family cross the river and boat is also with fisherman.
First children cross the river.later the son or daughter returns back gets down and the father crosses the river.then the other child returns with boat and mother goes and the remaining child returns with the boat at last both the children cross the river.