Note: the answer posted before which is now deleted was in error. Here is the correct solution: Let x be the number of years in the past the first time. Let y be the number of years in the future the second time. Let z be the number of years in the past the third time. A+B=48 A = 2(B-x) A-x = (1/2)(B+y) B+y = 3(A-z) A-z = 3(B-z) Those equations simplified and arranged in columns of like terms A + B = 48 A - 2B + 2x = 0 2A - B - 2x - y = 0 -3A + B + y + 3z = 0 A - 3B + 2z = 0 The solution by the augmented matrix method is A=30, B=18, C=3, D=36, E=12. Edwin