Hello Rohit
If there are different cases, we add them.
If there is one case, we multiply them.
For example:
If we need to find 4 cards of the same suit,
4 cards can be from Diamond, Spade, Club or Heart.
So, either we can take 4 cards from Diamond
or
4 cards from Spade
or
4 cards from Clube
or
4 cards from Heart
So, in this case, the combinations get added.
Now,
If we need to 4 cards, where 4 cards belong to 4 different suits.
Then, we choose 1 card from Heart
AND
1 card from Diamond
AND
1 card from Club
AND
1 card from Spade.
These, 4 cards make up 1 case.
So, we multiply them
Did you check out the video here ?
Written on Oct. 15, 2018, 5:45 p.m.