.7a + .25b + .3c = a .2a + .6b + .05c = b .1a + .15b + .65c = c WHERE a + b + c = 1 1st equation: .7a + .25b + .3c = a 2nd equation: .2a + .6b + .05c = b 3rd equation .1a + .15b + .65c = c 4th equation a + b + c = 1 Subtract a, b, and c from both sides of the first three equations, respectively, and you have this system: -.3a + .25b + .3c = 0 .2a - .4b + .05c = 0 .1a + .15b - .35c = 0 a + b + c = 0 The augmented matrix of this system is [-.3 .25 .3 | 0] [ .2 -.4 .05 | 0] [ .1 .15 -.35 | 0] [ 1 1 1 | 1] which is row equivalent to its row reduced echelon form: [1 0 0 53/111] [0 1 0 10/37] [0 0 1 28/111] [0 0 0 0 ] a = 53/111 b = 10/37 c = 28/111 Edwin AnlytcPhil@aol.com