The mean Intelligence Quotient (IQ) score is 100, and the standard deviation is 15. Calculate the z-score for Bill Gates' IQ score of 151.45.

To calculate the z-score, we use the formula:

z = (X - μ) / σ

where:
z = z-score
X = Bill Gates' IQ score of 151.45
μ = mean IQ score of 100
σ = standard deviation of 15

Plugging in the values, we get:

z = (151.45 - 100) / 15
z = 51.45 / 15
z = 3.43

Therefore, the z-score for Bill Gates' IQ score of 151.45 is 3.43.