How many two elements subsets from letters of english alphabet are the
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08 Aug 2023, 02:23
OE
We need to select two element subsets from all the English alphabet (i.e., 26)
In case of set: (2,5) is same as (5,2).
Therefore, order of elements does not matter. Hence, we use combination instead of
permutation.
Number of ways to select 2 elements from 26, when order does not matter is 26C2.
According to the question, we do not want a subset that includes ๐ and ๐ง.
There will be only one subset containing ๐ and ๐ง, i.e. (๐, ๐ง).
So, requirement is all possible sets except the subset (๐, ๐ง).
โTotal subsets โ 1 =\( C^{26}_1\)
\(26!/2!(26-2)!=325\)
Total subset = 325-1=324
B is the answer