John makes $40 a week from his job. He earns a raise and now makes $60 a week. What is the % increase? Choose the most appropriate option:
A) 16%
B) 16.66%
C) 18%
D) 21%
E) 50%
Increase = (20/40)*100= 
<gadget id="calculator">(20/40)*100</gadget>
<output>50</output>
50%.   50%
<result>E</result>
John makes $40 a week from his job. He earns a raise and now makes $60 a week. What is the % increase?