25.If you have 6 New Year greeting cards and you want to send them to 4 of your friends, in how many ways can this be done?
Solution:
We have to find number of permutations of 4 objects out of 6 objects.
This number is P46=6(6−1)(6−2)(6−3)=6*5*4*3=360
Therefore, cards can be sent in 360 ways.
So, using the factorial notation, this formula can be written as follows:
Prn=n!(n−r)!
Title : Permutation And Combination Q25
Description : 25.If you have 6 New Year greeting cards and you want to send them to 4 of your friends, in how many ways can this be done? Solution: ...
Rating : 5
