A contractor is engaged for 30days on the condition thathe receives Rs.25 for each day he works &is fined Rs.7.50 for each day is absent. He gets Rs.620 in all. For how many days was he absent?	Choose one:
A) 8 B) 10 C) 15 D) 7 E) 4
30 * 25= 
<gadget id="calculator">30 * 25</gadget>
<output>750</output>
750   620   -----------   130   25 + 7.50= 
<gadget id="calculator">25 + 7.50</gadget>
<output>32.5</output>
32.5   130/32.5= 
<gadget id="calculator">130/32.5</gadget>
<output>4</output>
4   4
<result>E</result>
A contractor is engaged for 30days on the condition thathe receives Rs.25 for each day he works &is fined Rs.7.50 for each day is absent. He gets Rs.620 in all. For how many days was he absent?