Logic / Unit 7 Logic 346 short lesson, about 20 seconds
Conditional Probability
Captions available
The idea
In general, P(A and B) = P(A) × P(B given A).
In practice
Two aces, no replacement: 4/52 × 3/51. The first draw changes the second's world.
Where people slip
P(B given A) and P(A given B) are different numbers — routinely, wildly different. Video 351 is built on that gap.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
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