Question

Carmen drove 864 miles in 12 hours.

Answer 1

what you would want to do first is find the unit rate by dividing 864 by 12, getting an answer of 72. (keep in mind that 72 is  how far Carmen is going in one hour) the you would divide 648 by 72 to get your final answer of 9.

Answer 2

9 hour is the answer hope it helps