Answer:
The z-score is -1.6 and it is not significant .
Step-by-step explanation:
Given : Test score = 48.4
Mean = 66
Standard deviation = 11
To Find :Find the z-score corresponding to the given value and use the z-score to determine whether the value is significant.
Solution:
Formula : [tex]z=\frac{x-\mu}{\sigma}[/tex]
[tex]\mu =66\\x=48.4\\\sigma =11[/tex]
Substitute the values
[tex]z=\frac{48.4-66}{11}[/tex]
[tex]z=-1.6[/tex]
So, the z-score is -1.6
Now we are given that Consider a score to be significant if its z-score is less than -2.00 or greater than 2.00.
Since -1.6>-2 and -1.6<2
So, It is not significant
Hence the z-score is -1.6 and it is not significant .