Complement: Marbles

P(NOT E) = 1 - P(E) with marble examples

Calculator Dice Coins Marbles Cards Learn

NOT a ColorNOT Color At Least OneAt Least Neither ColorNeither

Understanding "NOT a Specific Color"

What does "NOT red" mean?

If a bag has red, blue, and green marbles, "NOT red" means drawing any color except red. So you could get blue OR green — any non-red marble.

Why use complement?

Imagine a bag with 5 colors. "NOT red" means counting marbles of 4 different colors! Instead of adding all those up, just find P(red) and subtract from 1.

The Logic:

• Every marble is either red OR not red (no marble is both)
• P(red) + P(not red) = 1 (100% of possibilities)
• Therefore: P(not red) = 1 - P(red)

The Complement Rule:

Interactive Examples

Click a scenario to see the complement calculation:

Visual Representation

red: 3

blue: 4

green: 2

Total: 9 marbles

Step-by-Step Solution

Find P(red)

Apply complement rule

Result:

Key Insight

The complement approach is especially useful when "NOT something" has many possibilities. Instead of adding up all the other colors, just subtract the one you don't want from 1!