Independent Events

Definition

Independent Events in plain English

Two events are independent when one happening tells you nothing about the other, the first has zero effect on the odds of the second. Flipping a coin and then flipping it again is the classic case: getting heads the first time doesn't make heads any more or less likely next time, since the coin has no memory. This matters because when events truly are independent, you can find the chance of both happening by simply multiplying their individual chances (heads twice in a row is 1/2 × 1/2 = 1/4). The trap to avoid is assuming independence when it isn't there, like drawing cards without putting them back, where each draw really does change what's left.

Related GMAT terms

• Absolute Value
• Arithmetic Mean
• Composite Number
• Discrete Data
• Discriminant
• Domain
• Exponent
• Factorial
• Greatest Common Divisor (GCD)
• Inequality