The state test scores for 12 Randomly selected high school s

The state test scores for

12 Randomly selected high school seniors are shown on the right. Complete parts (a) through (c) below.

Assume the population is normally distributed.  

(a) Find the sample mean.=

1425       1226       985

691          728         831

721          742          547

624           1448       946

Solution

Getting the mean, X,      
      
X = Sum(x) / n  

As
  
Sum(x) =    10914  

And

n =    12  

Thus,      

X =    909.5   [ANSWER]