could someone please explain groups n parcels(ordered/non odered) n grouping to me??n why do we use multinomial theorm for problems which have random selectionsplz explain in simple lay man words.. thnx in advance!

Dear student,

The following is the multinomial formula or theorem, also called the Polynomial Theorem:
[1.1]
While it looks oppressive, it is easy to prove and also easy to use. In 1.1, the a's are terms. n is an integer. The m's are the number of each term selected.
The multinomial coefficient can be written:
[1.2]

(Where the sum of the m's is equal to n).
For instance:
[1.3]

Therefore, the Multinomial Theorem can be written: