by Raabi Anony
(Karachi, Pakistan)
Hello everybody
It is my very first posting and hope receiving help and guidance from the Math Geeks. Here is my very 1st problem:
I have 2 equal sets of numbers 1 to 6 as below:
A = {1, 2, 3, 4, 5, 6}
B = {1, 2, 3, 4, 5, 6}
How many unique pairs of numbers can be made out of these 2 sets, like;
(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6),
(2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6),
(3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6),


(6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)
While manually doing, I get total number of 36 pairs and after deducting the repetitions, I get 32 pairs. But, by using the Combination Formula 12C2 (12 numbers taken 2 at a time), I get 66 pairs. Where am I wrong!
Actually, I want to solve this problem for a larger number of sets, like 10. I will appreciate clearing my confusions and suggesting the better algorithm, if any.
Please note that I am interested in the number of pairs only, just for a general purpose, without getting into any definition of Sets or the Ordered Pairs etc.
Thanks in anticipation.
Raabi
Comments for Combinations of Numbers






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