A milkman has 2 varieties of milk-water solution, solution A has 65% pure milk and solution B has 78% pure milk. He is mixing x mL of solution A with y mL of solution B such that the resultant solution has no less than 70% pure milk and no more than 72% pure milk. If y can take any value between 625mL and 630mL, both inclusive, what is the difference between the minimum and maximum value x can take? It is given that x and y are both integers.