Question

20 is what percent of 50?

Answer 1

50 --- 100%
20 ---  x%

x = 20*100 / 50 = 40%

Answer 2

20/50 = x/100
cross multiply
(50)(x) = (100)(20)
50x = 2000
x = 2000/50
x = 40......so 20 is 40% of 50