Question

2.Two people out of a group of 75 will win tickets to an upcoming concert. How many different groups of two are possible?

Answer 1

2775

Step-by-step explanation

We have to find how many combinations of two people are possible since order does not matter. This is because both people will win a ticket, it does not matter which one is picked first,

`_2C_(75)=(75!)/(2!(75-2)!)=(75!)/(2!\cdot73!)=(75\cdot74\cdot73!)/(2!\cdot73!)=(75\cdot74)/(2)=2775`

Hence, 2775 groups of two people are possible.