Solve this Time and Work question: Meera and Pooja can audit a set of files in 20 days. Pooja and Nida can audit the same set in 30 days, while Nida and Meera can finish it in 40 days. How many days will Meera take if she completes the entire audit alone?

The verified answer to “Solve this Time and Work question: Meera and Pooja can audit a set of files in 20 days. Pooja and Nida can audit the same set in 30 days, while Nida and Meera can finish it in 40 days. The question-specific working supplied with the item states: Let Meera, Pooja and Nida have daily rates M, P and N. Then M + P = 1/20, P + N = 1/30, and N + M = 1/40. Add the first and third equations and subtract the second: 2M = 1/20 + 1/40 - 1/30. Hence Meera alone completes the audit in 48 days. This working identifies the relevant work-rate equation and connects the given information to the required result. After applying the verified rule, the required value or position is 48 days. The alternatives 54 days, 42 days and 45 days fail because each breaks at least one stated condition, transition, direction or arithmetic step. A plausible-looking option is not sufficient unless it reproduces the complete work-rate equation. This full replay leads only to 48 days, so option A is uniquely correct. The method is transparent, question-specific and suitable for SSC, Railway, Banking, Defence, State and other competitive examinations.