1. If the question asks: “Find the probability if...”
Does the question say it is normally distributed,
or is a mean and a standard deviation given?
Yes No
Does the question have a population standard deviation or variance?
= ?
Yes No
Is there a sample given in the question?
n = ?
Yes No
Normal distribution
Student t distribution
Is there an average rate?
Poisson distribution
Use Poisson tables or excel.
Can only 2 things happen, are there a set number of trials? Does the probability of a success remain constant?
Binomial distribution
Use binomial tables or excel
If there are many probabilities, it could be a tree diagram and may have conditional probability.
Yes No