Being a mathematician, I am familiar with probability calculations, but I need to ask a question related to investments and probability, and how this is handled seen from an economics view.
Given a project which involves two tasks, task 1 and task 2. Developing task 1 cost X dollars, while developing task 2 takes Y dollars if developed at the same time as task 1 and Z dollars if developed at a later stage.
The probability that we actually need Task 2 i 70%
What is the the "probable cost" of implementing Task 1 and 2 at the same time. vs. Task 1 and then Task 2 with a certain probability. And what is this called in economics? Probable cost? Estimated cost??