The length of pregnancy for the Asian elephant has an approximately normal distribution with an average length of 609 days and standard deviation of 31 days. 10. How long do the longest 5% of all elephant pregnancies last? 11. What percent of the elephant pregnancies last between 600 and 615 days? 12. The shortest 20% of all elephant pregnancies last fewer than how many days? 13. The middle 50% of all elephant pregnancies fall between how many days?