|  |  |  |  |  |  |  |  |  |  | 
   
    | q | P = the probability that a randomly selected value of a
    variable X falls 
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    |  | between a and b. 
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    |  | 
   
    | f(x) = the probability density
    function. 
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    |  | 
   
    | q | The probability function has to be integrated over distinct limits
    to 
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    |  | obtain a probability. 
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    |  | 
   
    | q | The probability for X to have some particular value is ZERO. 
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    |  | 
   
    | q | Two important properties of the probability density function: 
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    |  | 
   
    | (1) f(x) ¾ 0 for all x within the domain of f. 
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    |  | 
   
    | (2) 
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