What day was it on 6 November 1907?

Question

My class were set this and I have no idea how to go about it. We have to show full working too. Surely there's a better way than counting all the way down?

Answer 1

Yes there is a better way than counting.
Because you have a leap year every four years, you can say that there are 365.25 days per year, as long as you deal in years that are multiples of four (which I will be doing).

So, that means there are 52 + (1.25/7) weeks per year.
This is the same as 52 + (5/28) weeks per year.
As a top heavy fraction, this is 1461/28 weeks per year, and therefore there are 1461 weeks in 28 years. This is relevant because it is an exact number of weeks, the actual number 1461 doesn’t matter. This means that exactly 28 years ago, on 6 November, it was a Monday like it is today.
So, 6 November 1978 was a Monday.
6 November 1950 was a Monday.
6 November 1922 was a Monday.
6 November 1894 was a Monday.

We have slightly overshot now, so we need to add on years. (I did this because it is easier to add than subtract, plus 1894 is closer to 1907 than 1922.)
In 4 years there are 208 weeks and 5 days (I found this by multiplying 52 + (1.25/7) by 4 to get 208 + (5/7) which is equivalent to 208 weeks and 5 days.)

So, 208 weeks after 6 November 1894, the date is 1 November 1898, also a Monday (because it’s an exact number of weeks later). 5 days later, it is a Saturday, on 6 November 1898.
You use the same process to find that it is a Thursday on 6 November 1902, and that it was a Tuesday on 6 November 1906.

Since neither 1907 nor 1907 was a leap year (1904 and 1908 were), 365 days later it will be 6 November 1907.
365 days is 52 weeks and 1 day. So, 52 weeks later, it is a Tuesday and the date is 5 November 1907, and the next day is 6 November 1907, and it’s a Wednesday.

So on 6 November 1907, it was a Wednesday.

Actually there is a slight problem with this method, because 1900 was not actually a leap year, but in this case it did not matter because the date is after 1900. You would have to adjust it very slightly for dates before 1900.

Answer 2

It's all about division by 7 and remainders...

Start with the number of days in a year... 365. If you divide by 7, you get a remainder of 1. That means in normal years, the day changes by 1 day. So this year 6 November is a Monday, but last year it was a Sunday and next year it will be a Tuesday.

If a leap year is involved, there are 366 days. If you divide by 7, you get a remainder of 2. That means a leap year will change the day by *2* days.

Let's start with 6 November 2006 being a Monday.
That makes 6 November 2007 being a Tuesday.

Now work backwards for exactly 100 years.

Subtract 1 day for each year.
Subtract 1 additional day for each leap year.

So subtract 1 for each year (100) and subtract another 1 for each leap year (100/4 = 25). That's a total of 125 days difference.

How do you subtract 125 days from Tuesday??? Well, divide it again by 7. This gives you 17 with a remainder of 6. All you care about is the 6. So subtract *six* days.

6 days before Tuesday, is Wednesday...

The answer is that 6 November 1907 was a Wednesday.

Answer 3

11/6/1907 was a Wednesday

Answer 4

Wednesday

Answer 5

99 yrs x 365 days = 36135 days
add number of leap years (25) = 36160 days
divide by 7 = 5165 remainder 5
since today is monday and you are going backwards you assign monday = 0, tuesday = 6, wednesday = 5, tuesday=4, .......sunday=1
whatever your remainder is, is the day of the week it was.
So in this case it was 5 = WEDNESDAY.

Answer 6

Wednesday...

Answer 7

wednesday in U.S.