If a,b>1 are integers satisfying 11(a-1) = 13(b-1), find the minimum value of a+b.
The equation implies that (a - 1) is a multiple of 13 and (b - 1) is a multiple of 11.
The smallest possible a + b occurs when a - 1 = 13 and b - 1 = 11, which means min(a + b) = 25.
