Too early for a puzzle?
I know it is only Tuesday but I am on my flight back home and there are two of my friends who have sent me puzzles that I thought can be posted here…
This one comes courtesy of Amrith Kumar. I sent him an answer – but I have not received confirmation whether I am right or not. So, we might have to wait till he publishes the answer.
Think of all the 4 digit numbers ( leading 0s count). Essentially 0000 to 9999. Now pick only those numbers where the first two digits add up to the same number as the last two digits. So 1533 qualifies as does 0312 and so on.
You have to prove that the total of all such numbers (if you add them up) is divisible by 3 as well as 11.