There is a chicken, a bag if rice and a fox that need to get to the other side of the river by boat. There is only one boat that can only take one thing at a time across the river. If the fox and the chicken are left by them selves on one side of the river, the fox will eat the chick, and if the chicken and the bag of rice are left, then the chick will eat the rice. How do you get all of them to the other side, with all of them alive?
You take the chicken across, then you take the bag of rice across. After, you take the chicken back, take the fox across, then you bring the chicken back and you've done the whole thing.