Werner's salary is 20% of his boss's salary. By what percentage should Werner's salary increase to become equal to his boss's salary?
W = .2 B
W/.2 = B
or B = 5W 5 is 500% this situation comes up often when dealing with % on this forum
while Boss's salary is 500% of Werner's it would take a 400% INCREASE from his present salary to match B
i.e. W + 400% * W = B
5W = B