SOLVING PROBLEMS MEAN VARIANCE STANDARD DEVIATION

Which of the following represents the expected value of the discrete random variable?

• mean          

• median     

•    mode       

•   variance

Which of the following statements does not describe the value of the standard deviation?

• A small standard deviation (or variance) means that the distribution of the random variable is narrowly concentrated around the mean.

• A large value of standard deviation (or variance) indicates that the distribution is spread out, with some chance of observing values at some distance from the mean.

• Standard deviation is obtained by getting the square root of the variance.

• It is obtained by squaring the variance

What can we generate if we take the summation of the product of each value assigned to the random variable and its corresponding probability?

• Expected Value   

• Probability value    

• Standard Deviation  

• Variance

Suppose that a coin is to be tossed four times, and let X represent “the number of TAILS that can come up”, what are the possible values of the random variable X?

• 0       

•                 0,1             

•          1, 2,3              

• 0, 1, 2 ,3, 4

In the 50 items test, Miss Santos, a Mathematics teacher, claimed that most of the students’ scores lie closer to 40. In this situation, which of the following terms parallel to the score of 40?

• Expected Value or Mean    

• Median    

• Standard Deviation   

•  

  Variance