TOPIC: Project Risk Management Help

Hello, I am working through the PMBOK and have reached section 11.4.2.2, modelling and simulation. I understand the concept of what they trying to show however, not the math. Using the data they provide and the formula for probability of the mode on a cumulative curve (c-a/b-a) I arrive to 27% instead of 12% as in the PMBOK.

Am I making a mistake with my logic?

Nick,

Don't get too far into the weeds here, there won't be any complex math required on the exam involving modeling and simulation. Simply understand the concepts and you will be fine.

- Steven