Compare your answers.

  1. Determine the probability that a data value from a normal distribution will have a z-score between 1.41 and 2.03.

    The z-score tables can be used to determine that the area to the left of 1.41 is 0.9207 and the area to the left of 2.03 is 0.9788.






    The area between these two values can be found by finding the difference between them.
    0.9788 - 0.9207 = 0.0581



    The probability that a data value will have a z-score between 1.41 and 2.03 is 0.0581 or 5.81%.


  2. Determine the z-score above which 65% of data lies.

    65% of the data lies above the z-score, so 35% must be below (to the left) of it.



    Find the value closest to 0.35 on the inside of one of the z-score tables to determine the z-score.



    The z-score is -0.39.

 

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