To determine the day of the week on 8th February 2004, given that 8th February 2005 was a Tuesday, we follow these steps:

Step 1: Check if 2004 was a Leap Year

2004 was a leap year (divisible by 4).

Leap years have 366 days, meaning they have 2 odd days (since 366 ÷ 7 leaves a remainder of 2).

Step 2: Count Back to 8th February 2004

Since 2004 was a leap year, it had 2 extra days compared to a normal year.

Moving back one year (from 2005 to 2004) means we subtract 2 days from Tuesday.

Step 3: Calculate the Day of the Week

8th February 2005 was a Tuesday.

Subtracting 2 days (because 2004 was a leap year):

Monday → Sunday → Saturday

Final Answer:

The day on 8th February 2004 was Sunday.