If July 3rd, 1983 was a Sunday, then what day of the week was October 11th, 1983?

To find out the day of the week for October 11th, 1983, we can use the concept of "odd days". Odd days are the number of days more than the complete number of weeks in a given period. Here are the steps:

1. Count the number of days from July 3rd, 1983 to October 11th, 1983.

July has 31 days, so there are 31 - 3 = 28 days remaining in July after the 3rd.

August has 31 days.

September has 30 days.

And we're looking for the day on October 11th, so we'll add 11 days for October.

Adding these up, we get 28 (July) + 31 (August) + 30 (September) + 11 (October) = 100 days.

2. Divide the total number of days by 7 (since there are 7 days in a week) to find out how many complete weeks there are and what the remainder is.

100 ÷ 7 = 14 remainder 2.

This means there are 14 complete weeks and 2 odd days from July 3rd, 1983 to October 11th, 1983.

3. Since July 3rd, 1983 was a Sunday, we can add the number of odd days to this to find out the day of the week for October 11th, 1983.

Sunday + 2 odd days = Tuesday.

So, October 11th, 1983 was a Tuesday.