Decision Support Puzzles for Applied Mathematicians
You find yourself washed up on a deserted island with no water, shelter, or food. In order to survive you need to quickly secure a water source, build a shelter, and find a reliable food source (in that order).
Each day you will tackle these tasks one at a time until they are completed. The probability of you completing a task is outlined in the accompanying table. For example, if you attempt to secure a water source on a particular day, you have a 20% chance of completing that task on that day.
Each day that you have not completed the task, there is a corresponding risk of death (also shown in the table). Your daily overall probability of death is calculated by summing up the probabilities of tasks that are not completed. For example, if you have secured the water source and built your shelter, then your daily probability of death is 5% (because you have not yet secured the food source).
Once you have completed the three tasks, your survival rate becomes 100%.
Question: What is the probability you will survive?
Send your answer to firstname.lastname@example.org by June 15th, 2015. The winner, chosen randomly from correct answers, will receive a $25 Amazon Gift Card. Past questions can be found at puzzlor.com.