Answer :
There are an infinite number of them.
Here are a few:
4/10
6/15
8/20
10/25
12/30
14/35
16/40
18/45
20/50
Also 318/795 .
Here are a few:
4/10
6/15
8/20
10/25
12/30
14/35
16/40
18/45
20/50
Also 318/795 .