Puzzle – Four Adventurers and a Small Canoe

There is a small canoe that is used to cross a river. The canoe can hold at most 100 kg of weight. Now, there are 4 adventurers who are in a panic situation as in they need to cross the river. Among the 4 adventurers, Alex weighs 90 kg, Brook weighs 80 kg, Chris weighs 60 kg and Dusty weighs 40 kg. Also along with them, they have all over respective luggage of 20 kg. Will they be able to cross the river and return home safe, but wait how?

Solution:

The solution in 9 steps/images

So the problem is, they all need to cross the river in a way that the overall weight is less than the boat’s total capacity. We need to find an efficient way to solve the problem. There may be a couple of solutions that work properly, one of them is discussed below:

• First Chris and Dusty cross the river (combined weight is 100kg),
• Next, Dusty(40 kg) returns,
• Next, Alex(90kg) cross the river,
• Chris returns then,
• Chris and Dusty cross the river again,
• Dusty(40 kg) returns then,
• Brook(80kg) crosses the river with supplies (combined weight 100 kg) then,
• Chris(60kg) returns then,
• Now at the final, Chris and Dusty cross the river again.