6 machines : 5 days 3 machines : 10 days (half the amount of machines means double the work per machine so double to time) 1 machine : 30 days (now I know the time it takes for 1 machine to complete the task I can work out how long it would take 10 to) So if I multiply 1 by 10, I divide 30 by 10 giving my the ratio 10 machines : 3 days
