Distributions of gestation periods (lengths of pregnancy) for humans are roughly bell-shaped. The mean gestation period for

Question:

Distributions of gestation periods (lengths of pregnancy) for humans are roughly bell-shaped. The mean gestation period for humans is 272 days, and the standard deviation is 9 days for women who go into spontaneous labor. Which is more unusual, a baby being born 9 days early or a baby being born 9 days late? Explain