I am wondering how I would calculate the standard deviation of a distribution when the values given are as below:
z = -1.08
xi = 120
x_bar = 122
proportion = .14
The missing element here is the standard deviation.
z-score:
z = (xi - x_bar) / std_dev
Using the available data - is there a way to rearrange it to solve for standard deviation?
Using algebra:
z = (xi - x_bar) / std_dev
z(std_dev) = (xi - x_bar)
-1.08 * (std_dev) = -2
-1.08 / -1.08 = -2 / -1.08 # divide both sides by z-score
std_dev = 1.85