A boy has 9012 steps in how many different ways can be selected trouser and shirt
Answers
Answer: 10×10×10=103=100010×10×10=103=1000
The number of permutations of nn distinct objects with replacement is n!n!
e.g. Say I have 5 different books and I need to place them all on a bookshelf in 5 places. How many ways can I do this?
So you can choose from 55 books in the first place. You have 44 books left. Now you can place 44 books in the second place. Do you understand that we are not replacing the books. Once we place one our sample size decreases.
Here is your answer mate...✌✌✔
There are 9 trousers and 12 shirts.
First he needs to select a trouser and then he will select a shirt.
A trouser can be selected in 9/(9+12)= 9/21= 3/7 ways.
A shirt can be selected in 12/(9+12)=12/21=4/7 ways.
As it is both of them i.e., a trouser and a shirt so the values should be multiplied.
That is 3/7 × 4/7 = 12/49.
There fore he can select a trouser and a shirt in 12/49 ways .