z = (x - μ) / σ

2 = (x - 72) /6

multiply both sides by 6

12 = x-72

add 72 to both sides

12+72 = x

x=84

z = (x-μ)/σ

x = μ+zσ

72+2(6) = 72+12 = 84

72 +6(2) = 90

Z = (X - mean)/SD

2 = (X - 72)/6

12 = X - 72

X = 84

Rule

Z = (X - mean)/(standard deviation)

Z score of 2 means 2 standard deviations above the mean.

Take the standard deviation, multiply it by 2 and add it to the mean.