\(A\) and \(B\) are two laborers who have been given the task to build a house. \(A\) can build a house in \(20\) days while \(B\) can build it in \(30\) days. But \(B\) went rogue and instead of building the house, he starts breaking it at the same rate. If \(A\) starts the work on the \(1st\) day and they work alternately, in how many days will the house get built? (Assume once the house gets build, they will stop working).
A. \(60\) days
B. \(115\) days
C. \(120\) days
D. \(140\) days
E. \(121\frac13\) days
Answer: B
Source: e-GMAT