Answer & Explanation
A) Rs. 80
The servant worked for 9 days instead of 12 days, he should receive 9/12 of his total payment
Let the price of 1 shirt be Rs. S
i.e., 3/4 (400 + S).
However, the question states that the servant receive Rs. 280 + S where S is the price of the shirt.
By equating the two equations we get 3/4 (400 + S) = 280 + S.
Therefore, Price of the shirt S = Rs. 80.