Work Shown:
x = 108 is the raw score we want to transform
mu = 104 is the mean
sigma = 1.9 is the standard deviation
z = (x-mu)/sigma
z = (108-104)/1.9
z = 4/1.9
z = 2.10526315789473 which is approximate
z = 2.11 rounding to two decimal places
I'm rounding to two decimal places because many z tables will work with this level of precision.
