Answer:
ways
Step-by-step explanation:
Given that a shelf contains n separate compartments. There are r indistinguishable marbles
The marbles are identical so they can be placed in any order.
Let us consider the places available for placing these r marbles
No of compartments available =n
Marbles to be placed = r
Since marbles are identical and order does not matter
number of ways the r marbles can be placed in the n compartments
= nCr
=