A mail handler needs 3 hours to sort the mail. His assistant takes 6 hours to sort the mail. How many hours will it take for both of them working together to sort the mail?  Choose the correct answer:
A) 3
B) 2
C) 1
D) 2 1/2
E) 1 1/5
Work hrs=A2/(A+2)= 18/9= 
<gadget id="calculator">18/9</gadget>
<output>2</output>
2   Answer is 2
<result>B</result>
A mail handler needs 3 hours to sort the mail. His assistant takes 6 hours to sort the mail. How many hours will it take for both of them working together to sort the mail?