### Birthday Equations

This idea started as a stupid facebook status but is starting to sound like quite a useable rich task.

I noticed that my birthday this year (today: 22/02/11) forms an equation 22/2=11. I invited my facebook friends to work out when the next time was that their birthday would form an equation. Quite a few people replied, including non maths teachers.

Then Lydia posed an interesting question: are there people out there whose birthdays will never form an equation?

Initially I thought no, because I thought addition would always work. But if you were born 01/01/03 then you'd never have a birthday equation.

So far in all my 22 years, I've only had two birthday equations. 22/02/00 was one because 22 mod 2 = 0.

When are my next ones?:

22/02/20 22-2=20

22/02/24 22+2=24

22/02/44 22*2=44

I'm having trouble thinking of other operations. 22 choose 2 is 231 which is too big. 22^2 is 484 which is too big.

I really know how to enjoy my birthday don't I?

Emma x x x

PS this rich task is copyright Team Hopper. When Team Hopper publishes their first book, this will be one of the activities included. You may not reproduce this task without the permission of Team Hopper.

## One comment

Hi Emma,

Many Happy Returns of the Day.

I hope you have had the day off.

Have a great evening.

Laura

22 Feb 2011, 18:10

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