In the problem, we're told that and

Let be the random variable that represents the length of an elephant's pregnancy.

Thus, we are to find .

To solve this problem, we must incorporate the -score.

We know .

Thus,

Now you can use the standard normal distribution tables to see that or 0.95%.

Using a similar idea, you can show thatWhat % of pregnancies last between 510 and 540 days?

I leave it for you to determine this value.

I'm not quite sure what to make of this part. Maybe someone else can help you with this.How short do the shortest 10% of all pregnancies last?

Thank you in advance!!!!!

I hope what I've helped with makes sense!