Question

how would you calculate her due date what is her due date

Answer 1

Answer ;

These can be calculated by certain kind of day calculation on the basics of last menstrual period date.

The first thing you should do would be noticing her first day after the last menstrual period.
By taking that into account and adding with 40 weeks you will probably find the due date of her delivery.

In simple you can find the exact date, by the adding the first day with nine months that are coming next .
If suppose 27th may would be the first day of the last menstrual cycle, then add these date with nine month, that would be the February 27, after getting these data just add extra 7 days with that date And that date would be the expected due fro her delivery.