Can someone explain how I missed this question.

Sample has a mean of 47 and a standard deviation of 9. Find the z-score for each value of x=53.(give answer correct to 2 decimal places) I did it this way and missed it 53-47divided by 9 = 0.666 and I put 0.6 for the answer. Did I use the wrong formula??? Because I missed all of them using this formula.

yes, you need to see where in the Z table .666σ occurs.

Take a look at
http://davidmlane.com/hyperstat/z_table.html
to play around with Z values