L3 - DRV

• The Mean µ of a discrete random variable is the central value or average of its corresponding probability mass function.
• The mean is also called as the?

  Expected value
• What is step one in finding the mean?

  Construct the probability distribution for the random variable X representing the number of items that the customer will buy.
• What is the second step in finding the mean?

  Multiply the value of the random variable X by the corresponding probability.
• What is the last step in finding the mean?

  Summation of the results obtained in Step 2.
• The variance and standard deviation are two values that describe how scattered or spread out the scores are from the mean value of the random variable
• What is step one in finding the variance and standard deviation?

  Find the mean of the probability
• What is step two in finding the variance and standard deviation?

  Subtract the mean from each value of the random variable X
• What is step three in finding the variance and standard deviation?

  Square the result obtained in Step 2.
• What is step 4 in finding variance and standard deviation?

  Multiply the results obtained in Step 3 by the corresponding probability.
• What is the last step in finding the variance and standard deviation?

  Summation of all the results obtained in step 4