56% of what equals 21.84

100%/x%=56/21

(100/x) * x = (56/21) * x - we multiply both sides of the equation by x

100=2.66666666667*x - we divide both sides of the equation by (2.66666666667) to get x

100/2.66666666667=x

37.5=x

x=37.5

now we have:

21 is 37.5% of 56