2/5
2 over 5 is an equivalent fraction for 20 over 50.
2 equivalent fractions of 20 over 50 = 2/5, 40/100
There is no "the" equivalent fraction since there are infinitely many of them. 20/50 or 2000000/5000000 are two examples.
Don't do it
37 over 50
0.22
45/50 = 9/10
11-50 or 11 over 50
4/50 = 2/25
50/200, 18/72
10/9
7/10