Lol

I use the cross mulitplication method for percentages. It is easy. 5600 is 100% and you want to calculate 30%, thus (5600*30)/100= 1680 your answer. 

 

Or you could mean that 5600 is 30% (unlikely), but lets calculate. in this case you want to calculate 100%. (So 5600*100)/30= 18666,6667

This is very easy and simple way to solve such problems:

30% means =30/100 =0.30, then:

0.30 x 5,600 =1,680  and that is it.