A can do a job in 15 days and B can do it in 30 days. A and B working together will finish twice the amount of work in days? Choose the correct option:
A) 20
B) 22 1/2
C) 22 1/0
D) 22 1/9
E) 22 1/1
1/15 + 1/30 = 3/30 = 1/10   10= 10 *2= 
<gadget id="calculator">10 *2</gadget>
<output>20</output>
20 days   20nswer: 20
<result>A</result>
A can do a job in 15 days and B can do it in 30 days. A and B working together will finish twice the amount of work in days?