text: how manny hours will a plane take to go 1200 miles if it travels 450 miles in two hours? i really dotn understand it my answers are  a:2 3/4 b:4 1/2 c:5 1/3 d:9 e:12 if it goes 450 miles in two hours, that breaks down to 225 miles in one hour- or 225 per hour.  divide 1200 by 225 (because 225 is the per one-hour rate) and you get 5.33 hours.