A man has 9 shirt and 4 ties. How many different shirt and tie arrangements can be wear?
Solution:-
Multiplication Principle of Counting.
If a take consists of a sequence of choices in which there are p selections for the first choice, q selection for the second choice, r selection for the third choice, and so no, then task of making these selections can be done in
P*q*r*…
different ways.
There are only two choice to be made. First the man must select a shirt to wear, and then he has to select a tie.
There are 9 ways for him to select a shirt.
There are 4 ways for him to select a tie.
So, by the Multiplication Principle of Counting, there are 9 * 4 or 36 different shirt and tie arrangements from which to choose.