Three painters can paint three walls in three mins how many painters are needed to paint 27wall in 9 mins

There is 3 variables, the painters, walls and time. The problem is we need to know how many painters are needed. We know that increasing the walls will give us more painters. In this case, you need to divide the variable walls with time since it reversed so: 27walls / 9 minutesIt equal to: 3 walls/minute
Information provided is:3 painters= 3 walls/3 minutesEqual to : 3 paintes= 1 wall/minute
To make it 3 walls/minute, the painter needed will be:(3 walls/minute) / (1 wall/minute) x 3 painters= 9 painters
Answer is 9 painters