Question

Calculate the number of ways to form a set of three distinct items such that no two of the selected items are in the same row or same column

Answer 1

Answer:

1200

Explanation:

Order does not matter, if we said xyz order, it would still not make a difference if it was zyx or yzx hence we use the combination formula:

nCr = n! / r! * (n - r)!

where n= total number of items

r= number of items chosen at a time

Combinations are used when the order of events do not matter in calculating the outcome.

We calculate using the formula:

(30×20×12)÷3!=1200

There are therefore 1200 ways for the three distinct items to not be in same row or column