She drives at a rate of 75 miles per hour for three hours, so the first thing you'd do is 75 x 3.
75 x 3= 225
So, she traveled 225 miles to the airport.
Then, she travels at a rate of 400 miles per hour for 4 hours.
4 x 400 = 1,600
That's 1600 miles she traveled from the airport to her destination.
Now to find the total number of miles traveled, add 1,600 and 225.
Total distance traveled: 1825 miles.