Answer:
-1.1
Step-by-step explanation:
The z-score formula is expressed as;
z = x - m/s
x is the sample size = 495
m is the mean score = 550
s is the standard deviation = 50
Substitute inti the formula;
z = 495 - 550/50
z = = -55/50
z = -11/10
z = -1.1
Hence the z score is -1.1
