Almost all high school students who intend to go to college

Almost all high school students who intend to go to college take the SAT test. In recent years the mean SAT score (in verbal and mathematics) of all students has been around 900.

Solution

First, we get the z score from the given left tailed area. As          
          
Left tailed area = 1-0.1 =   0.9      
          
Then, using table or technology,          
          
z =    1.281551566      
          
As x = u + z * s,          
          
where          
          
u = mean =    904      
z = the critical z score =    1.281551566      
s = standard deviation =    153      
          
Then          
          
x = critical value =    1100.07739   [ANSWER]