# Group Theory

#### Doe

##### New member
Hello everyone i am new here and have i little problem xD
So the problem is:

Find an example of an infinity grupoid $$\displaystyle (G, *)$$ whose every real subgrupoid $$\displaystyle (H, *)$$ is:
a) infinit
b) finite

I thought in context of natural numbers, real numbers, set of all prime numbers with many different operations defined on it, but i still have no idea how to construct such structure... Thanks in advance.