Three containers X Y and Z are having mixtures of milk and water in the ratio 1 5 3 5 and 5 7 resp I...........

Three containers X, Y and Z are having mixtures of milk and water in the ratio 1 : 5 , 3 : 5 and 5 : 7 resp. If the capacities of the containers are in the ratio 5 : 4 : 5, then find the ratio of the milk to the water, if the mixtures of all the three containers are mixed together.