To find a relative date 90 days in the past from 25th January, you can use a simple manual calculation method. Firstly, identify the starting date which is 25th January. Then, subtract 90 days from it by performing basic arithmetic. By counting back day by day, you can determine the date that falls 90 days in the past.

To manually calculate it, start with 25th January as the reference date. Subtracting 90 days from it involves subtracting a total of three months (30 days each) from the date. Begin by subtracting 30 days to get to 25th December, then another 30 days to end up on 25th November. Lastly, subtracting the remaining 30 days leads us to the relative date 90 days in the past, which is 25th November.

Therefore, in this example, the relative date 90 days in the past from 25th January can be manually calculated as the 25th of November. This method is effective for determining dates based on specific offsets from given dates. It is a useful technique for various purposes, such as scheduling, planning, or historical analysis. Mastering this calculation can provide valuable insights and assist in better understanding timelines and elapsed durations.