### Intro to Probability

Lesson by Mike McGarry
Magoosh Expert

Summary
The introduction to probability as covered in this module provides a foundational understanding of probability as a ratio, the significance of randomness, and basic strategies for calculating probabilities.
• Probability is defined as a ratio or fraction representing the number of successes over the total number of outcomes, with values ranging between 0 (impossible) and 1 (certain).
• The concept of randomness in mathematics implies that while individual events are unpredictable, the overall pattern of events is predictable.
• A simple example of calculating probability is determining the likelihood of a month name containing the letter 'R', which is demonstrated to be 2/3.
• Listing all possibilities is introduced as an elementary strategy for understanding and solving probability problems, though it's acknowledged that more complex strategies will be needed for the GMAT exam.
• The importance of understanding both the unpredictability of individual events and the predictability of the overall pattern is emphasized in the context of randomness.
Chapters
00:00
Understanding Probability
00:20
The Ratio Nature of Probability
03:32
The Concept of Randomness