Statistics:
a person's standardized test score on a test is given by the function z(x) = x-25/40, where x is the actual score on the test.
a) if the person's actual score was 600, what is the standardized score?
b) find the inverse of z(x)
c) using the inverse, if the person's standardized score was 2.5, what was the person's actual score on the test?

your work:
a)

b) step 1: switch the x & y
step 2: solve for y

c)