Other Way to Solve Using Set Theory
R ( A B C D E )
with that 2^5 unique Subset Are possible but we want only those Subset which Contain Atleast 2 element then we remove subset with 0 element as well as Subset with 1 element
Subset with 0 element is 1
Subset with Only One Element is 5C1
ubset which Contain Atleast 2 element = 32 – 5 – 1
= 26
CORRECT ME if i am wrong..