Answer: 2.28%
Explanation:
μ = 71.8
σ = 3.4
X < 65
P(X < 65) = P (Z < 65 - 71.8/3.4) = P (Z < -2)
According to the table for the normal distribution attached, it will give us
P (z < Z < 0), this way, to find the P(Z < z), we need to do 0.5 - P:
0.5 - P(-2 < Z < 0) = 0.5 - 0.4772 = 0.0228
In percentage: 0.0228*100 = 2.28%