Respuesta :

16-20= 4 so 4/20 is 0.2 or 20%. To get percentage move decimal to the right two times :)
16
----
20   to make 20 100 multiply by 5 as we multiply denominator we multiply numerator

16 x 5       80
--------- =  -----   so the answer is 80%
20 x 5      100