Given Information:
- The day on 4th April, 1988, is a Monday.

To find:
- The day on 3rd November, 1987.

Analysis:
- We need to find the day of the week for a date that is before the given date.
- Since we have the day of the week for the later date, we can use the concept of counting the number of days between the two dates.

Solution:
1. First, we need to find the number of days between 3rd November, 1987, and 4th April, 1988.
2. We can break down the calculation into three parts:
- Count the number of days from 3rd November, 1987, to 31st December, 1987.
- Count the number of days from 1st January, 1988, to 3rd April, 1988.
- Add the above two counts to get the total number of days.
3. To count the number of days between 3rd November, 1987, and 31st December, 1987:
- November has 30 days, so subtract 3 from 30 to get 27 days.
- December has 31 days, so add 27 to 31 to get 58 days.
4. To count the number of days between 1st January, 1988, and 3rd April, 1988:
- January has 31 days, so add 31 to 58 to get 89 days.
- February has 29 days in a leap year (1988 is a leap year), so add 29 to 89 to get 118 days.
- March has 31 days, so add 31 to 118 to get 149 days.
- April has 3 days, so add 3 to 149 to get 152 days.
5. Finally, add the counts from step 3 and step 4 to get the total number of days:
- 58 + 152 = 210 days.
6. Now, we divide the total number of days by 7 (the number of days in a week):
- 210 ÷ 7 = 30 weeks.
7. Since we are counting forward from Monday, we need to add the remaining days to Monday:
- 210 - (30 × 7) = 0 remaining days, which means the day on 3rd November, 1987, is also a Monday.

Therefore, the day on 3rd November, 1987, is Monday.