A can do a job in 20 days and B can do it in 30 days. A and B working together will finish twice the amount of work in ------- days? Select the correct option
A) 14 days  B) 16 days  C) 24 days  D) 11 days  E) 19 days
24 days   1/20 + 1/30 = 1/12   12 *2= 
<gadget id="calculator">12 *2</gadget>
<output>24</output>
24 days
<result>C</result>
A can do a job in 20 days and B can do it in 30 days. A and B working together will finish twice the amount of work in ------- days?