What are the number of ways in selecting 5 elements from 25 unique elements? The order of the selected elements are not important?
I have 25 numbers, 1,2,3,4,5……23,24,25.
What are the number of ways a pair 5 elements be selected. The order of the selected elements are not important.
like the pair of 1,2,3,4,5 is same as 2,3,4,5,1
The order of the elements in the pair is not important.
How may number of pairs can be formed?
Best Answer
This is only $\binom{25}{5}$. Ok?