Respuesta :

31,61 ----- 436%
x ----------- 100%
------------------------

 x = 31,61*100/436 = 3161/436 = 7,25 

hope this will help you 
31.61 = 436% of x

31.61 = (436/100)*x

31.61 = 4.36x

4.36x = 31.61

x = 31.61 / 4.36

x = 7.25

31.61 is 436% of 7.25