Date value should be selected after X days if I select a value in above dropdown field

[Ajaygoud Gaddam]

We have Location field as drop-down field and date field. here we need if I select value XXX from Location the date field should be selected after 10 days and If I select YYY in the location the date field should be selected as 5 days after the current date. 

We are using JMWE any script can be shared which suits for this condition

Thanks,

Ajay