The exam scores among the college students in a particular c
     The exam scores among the college students in a particular country are normally distributed with a mean of 500 and a standard deviation of 100. What is the probability that a randomly selected individual from this population has a score at or below 600? 
  
  Solution
We first get the z score for the critical value. As z = (x - u) / s, then as          
           
 x = critical value =    600      
 u = mean =    500      
           
 s = standard deviation =    100      
           
 Thus,          
           
 z = (x - u) / s =    1      
           
 Thus, using a table/technology, the left tailed area of this is          
           
 P(z <   1   ) =    0.841344746 [ANSWER]

