A can do a job in 18 days and B can do it in 24 days. A and B working together will finish twice the amount of work in days?  Choose the correct choice from the following options
A) 22 1/6
B) 22 1/2
C) 20 4/7
D) 22 1/9
E) 22 1/1
1/18 + 1/24 = 7/72   72/7 = 72/7 *2 = 20 4/7 days   Answer: 20 4/7
<result>C</result>
A can do a job in 18 days and B can do it in 24 days. A and B working together will finish twice the amount of work in days?