Vanya is back with yet another task for you, and this time out, she has tried to make it more interesting for you. So, this is how it goes:
Vanya has some students studying in her class. For each students, she gives you $$3$$ pieces of information, i.e their Name, ID and Age.
Now, considering you have been given this information, Vanya needs to know from you the number of ways she can select $$2$$ distinct students, such that they share the same age. Can you help her out ?
Table : Students
$$ 1 \le Age \le 10 $$
$$ 1 \le | Name, ID | \le 20 $$
The ways Vanya can select $$2$$ students sharing the same age is :
So, the answer is $$4$$.