Answer
1) The proportion of the lengths of human pregnancies that are between 230 and 260 days is 0.3416.
2) The probability that a randomly select human pregnancy has its length between 230 and 260 days is 0.3416.
Work Step by Step
1) $\frac{lengths~of~human~pregnancies~between~230~and~260~days}{total~number~of~observed~pergnacies}=0.3416$
2) $P(230\lt X\lt260)=0.3416$
