To find a relative date 90 days in the future from 25th August, you can manually calculate it by adding 90 days to the given date. Start by breaking down the calculation: August has 31 days, so from the 25th, there are 6 days remaining. Adding 90 days would exceed August, moving into September where you would subtract those 6 days to advance to the next month. This method helps you accurately determine the future date.