About % of the area under the curve of the standard normal distribution is outside the interval z = [ − 2.04 , 2.04 ] (or beyond 2.04 standard deviations of the mean).

Question

What is the % of the area under the curve of the standard normal distribution is outside the interval z = [ − 2.04 , 2.04 ] (or beyond 2.04 standard deviations of the mean).

Answer 1

Since the normal distribution is symmetric, find the area to the left of z = -2.04 then double it. From the standard normal probability table P(z < -2.04) = 0.0207.