Going back to Republican's milk and water problem... hopefully you can follow it: X cups of milk------>xm X cups of wate----->xw Container 1: xm Container 2: xw Step 1: xm-1m, xw+1m (x-1)m xw+1m Step 2: (x-1)m+ (xw+1m)/(x+1) xw+1m-(xw+1m)/(x+1) {(x^2-1)m+xw+1m}/(x+1) {x(x+1)w+(x+1)m-xw-1m}/(x+1} Final: (x^2m+xw)/(x+1) (x^2w+xm)/(x+1) Since, coefficient of m in container 1= coefficient of w in container 2; They are equal...