Diana usually drives at an average rate of 30 mph. If she drives for 2 hours at a speed that is 10 mph greater than usual, what distance will she travel?
If Diana usually drives at an average rate of 30 mph, in 2 hours, she will travel 2*30 =<<2*30=60>>60 miles.
If Diana drives for 2 hours at a speed that is 10 mph greater than her usual speed, she will drive at 30+10 = <<30+10=40>>40 mph.
At 40 mph, the total distance Diana will travel in 2 hours is 2*40 = <<2*40=80>>80 miles. Answer: \boxed{80}.