The total number of ways to complete a process with multiple independent stages is the product of the number of choices at each stage.

Keyword: "And"

Formula:

Total Choices = m*n p ..........*1

m, n, p : Choices at Stage 1, 2, 3, etc.

For mutually exclusive events (cannot happen simultaneously), the total number of ways to perform either event is the sum of their individual ways. For non-mutually exclusive events, subtract the overlap.

Keyword: "Or"

Formulas:

Mutually Exclusive:

Total Ways = m + n

Non-Mutually Exclusive:

Total Ways} = m + n - Overlap

Calculate the number of desired outcomes by subtracting the number of unwanted outcomes from the total number of outcomes.

Logic Formula:

Desired Outcomes = Total Outcomes - Unwanted Outcomes

1 Use FCP for sequential "and" choices .

2 Use Rule of Sum for "or" choices .

3 Use Indirect Method when counting "not" cases is easier than direct counting.