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## Intro to Probability

Summary
The essence of probability in the GRE context is explored, emphasizing its definition as a ratio, the significance of randomness, and basic strategies for solving probability problems.
• Probability is fundamentally a ratio or fraction, representing the number of successes over the total number of outcomes, and must fall between 0 and 1.
• A probability of 0 signifies impossibility, while a probability of 1 indicates certainty, with most real-world probabilities lying somewhere in between.
• The concept of randomness in mathematics implies that while individual events are unpredictable, the overall pattern of events is predictable.
• Simple probability problems can sometimes be solved by listing all possible outcomes, though this method is not always feasible for more complex questions.
• Future discussions will introduce more abstract and general rules for solving probability problems beyond the basic strategy of listing.
Chapters
00:05
Understanding Probability
00:56
The Range of Probability
03:33
The Concept of Randomness
02:04
Basic Probability Strategies