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probability

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noun prob·a·bil·i·ty \ˌprä-bə-ˈbi-lə-tē\

Simple Definition of probability

  • : the chance that something will happen

  • : something that has a chance of happening

  • : a measure of how often a particular event will happen if something (such as tossing a coin) is done repeatedly

Source: Merriam-Webster's Learner's Dictionary

Full Definition of probability

plural

probabilities

  1. 1 :  the quality or state of being probable

  2. 2 :  something (as an event or circumstance) that is probable

  3. 3 a (1) :  the ratio of the number of outcomes in an exhaustive set of equally likely outcomes that produce a given event to the total number of possible outcomes (2) :  the chance that a given event will occur b :  a branch of mathematics concerned with the study of probabilities

  4. 4 :  a logical relation between statements such that evidence confirming one confirms the other to some degree

Examples of probability in a sentence

  1. There is a low probability that you will be chosen.

  2. There is some probability of rain tomorrow.

  3. With the dark clouds moving in, rain seems more like a probability than a possibility.

  4. The probability of a coin coming up heads is one out of every two tries.



15th Century

First Known Use of probability

15th century

Other Mathematics and Statistics Terms



PROBABILITY Defined for Kids

probability

play
noun prob·a·bil·i·ty \ˌprä-bə-ˈbi-lə-tē\

Definition of probability for Students

plural

probabilities

  1. 1 :  the chance of happening <The probability of rain is low.>

  2. 2 :  something likely <Rain is a probability.>

  3. 3 :  a measure of how likely a given event is <The probability of a coin landing face up is 1⁄2.>





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