Is 4 minutes on 700W microvave 1200W=?min.'s

It it takes 4.5 minutes to cook on a 700 watt microwave oven, how
many minutes would it take to cook the same item on a 1200 watt
microwave oven? Please show formula used.

I don't have a specific formula I just know that it'll take around 2 minutes if that on a 1200W microwave from my experiences.