3 pumps, working 8 hours a day, can empty a tank in 2 days. How many hours a day must 12 pumps work to empty the tank in 1 day?	Choose the correct answer:  A) 4  B) 10  C) 11  D) 12  E) 13
3 pumps take 16 hrs total (8 Hrs a day)   If 1 pump will be working then, it will need   16*3= 
<gadget id="calculator">  16*3</gadget>
<output>48</output>
48 hrs   1 pump need 48 Hrs   If I contribute 12 pumps then     48/12= 
<gadget id="calculator">  48/12</gadget>
<output>4</output>
4 hrs.   answer :4
<result>A</result>
3 pumps, working 8 hours a day, can empty a tank in 2 days. How many hours a day must 12 pumps work to empty the tank in 1 day?