What Is a Dependent Event?

What Is a Dependent Event?

An event is dependent if its probability is affected by whether or not another event has occured.

A Real Example of a Dependent Event

It is easier to understand a dependent event with an example.

Picking Cards

If a card is picked from a pack, 1 card is picked from a deck of 52 cards. The probability is 152.

If the card that has been picked is not put back into the deck, there will be 1 less card in the deck.

If a 2nd card is picked from the deck, 1 card is picked from a deck of 51 cards. The probability is 151.

Picking cards without replacement are dependent events.

Another Real Example of a Dependent Event

Picking colored marbles from a bag, without replacing them, gives another example of dependent events.

The slider below shows how the probabilities of picking a certain colored marble changes depending on whether that color has been picked before.

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See Also

What is probability?