how do you work out which day of the week a date falls on?

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999 mum
Posts: 422
Joined: Sun Feb 14, 2010 12:02 am

Re: how do you work out which day of the week a date falls o

Post by 999 mum »

TP123 wrote: Just a quick question - so if they asked "which day of the week wuold be his/her 35th birthday" then instead of adding 5 would you add 8?
In this case yes, because the dob was in a leap year after feb.

Suppose the dob had been jan 2004, then there would be a leap year for the first birthday and the fifth. So allowances would have to be made for where in the four year cycle you were.
TP123 wrote:And if he/she was born on Monday and the remainder was 6 then would the birthday fall on Sunday.
Yes.
ConcernedDad
Posts: 204
Joined: Wed Jan 25, 2012 8:43 pm

Re: how do you work out which day of the week a date falls o

Post by ConcernedDad »

Was the day of the week that he was born on given?

If so,
1. then the number of days can be calculated by 21*365+5.
2. Divide the total by seven,
3. What ever the remainder is count on that many days of the week.

I think this would work, but I have not worked it out or checked it. (Sorry)

Hi, I am new to this forum. My DD is going through the 11+ process, and I wish I came across this forum much earlier :(

Maybe I can suggest a small change in the above method :

If so,
1. Calculate 'Number of Years + Number of Leap years' between the 'start date' and 'end date' ('21 + 5' in OP's example)
2. Divide the total by seven, (26 / 7 in the example)
3. What ever the remainder is count on that many days of the week.

As '365 remainder 7 is 1', you need to multiply with 1 instead of 365 to save time.
TP123
Posts: 466
Joined: Fri Nov 20, 2009 11:46 am

Re: how do you work out which day of the week a date falls o

Post by TP123 »

999 mum wrote:
TP123 wrote: Just a quick question - so if they asked "which day of the week wuold be his/her 35th birthday" then instead of adding 5 would you add 8?
In this case yes, because the dob was in a leap year after feb.

Suppose the dob had been jan 2004, then there would be a leap year for the first birthday and the fifth. So allowances would have to be made for where in the four year cycle you were.
TP123 wrote:And if he/she was born on Monday and the remainder was 6 then would the birthday fall on Sunday.
Yes.
Thanks!
999 mum
Posts: 422
Joined: Sun Feb 14, 2010 12:02 am

Re: how do you work out which day of the week a date falls o

Post by 999 mum »

ConcernedDad wrote:Hi, I am new to this forum. My DD is going through the 11+ process, and I wish I came across this forum much earlier

Maybe I can suggest a small change in the above method :

If so,
1. Calculate 'Number of Years + Number of Leap years' between the 'start date' and 'end date' ('21 + 5' in OP's example)
2. Divide the total by seven, (26 / 7 in the example)
3. What ever the remainder is count on that many days of the week.

As '365 remainder 7 is 1', you need to multiply with 1 instead of 365 to save time.
Concerned Dad
I agree with you, and if I was doing it I would use your method. But I don't think my DCs would understand it yet, whereas working out the total number of days is something that they would.

I believe they should understand the logic of doing maths rather than the rules. (there have been too many times when they have said well teacher says so without any understanding)
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