A can do a work in 9 days. B can do the same work in 18 days. If both A & B are working together in how many days they will finish the work?
Choose the correct choice from the following choices
A) 3
B) 5
C) 4
D) 2
E) 6

Rationale: "a rate = 1 / 9 b rate = 1 / 18 ( a + b ) rate = ( 1 / 9 ) + ( 1 / 18 ) = 1 / 6 a & b finish the work in 6 days correct option is e"
Answer: E