Question

10 people exchange greeting at a business meeting. how many greeting are exchanged, if everyone greets each other once?​

Answer 1

Step-by-step explanation:

using n(n-1)/2

n=10

10*9/2=45

I hope you will understand it

Answer 2

Answer:

45

Step-by-step explanation:

Each of the n persons greets (n-1) persons.

The total no. of greets is n*(n-1). [n people greet (n-1) people]

Note that , in this we have considered each greeting twice.

( If A and B shake hand, it is counted for both A and B).

Hence, the total no. of greets should be {n*(n-1)}/2.

replacing n by 10, we get      {10*(10-1) } /2

                                            =(10*9)/2

                                            =90/2

                                            =45.      (Answer)

                         

                                               THANK YOU...