A can do a piece of work in 30 days. He works at it for 5 days and then B finishes it in 20 days. In what time can A and B together it?	Select:
A) 16 2/3 days
B) 13 1/3 days
C) 17 1/3 days
D) 16 1/2 days
E) 17 days
5/30 + 20/x = 1   x = 24   1/30 + 1/24 = 3/40   40/3 = 13 1/3 days   ANSWER:13 1/3 days
<result>B</result>
A can do a piece of work in 30 days. He works at it for 5 days and then B finishes it in 20 days. In what time can A and B together it?