let

p = the speed of the plane

c = the speed of the car

the speed of the plane was 190 mph faster than the speed of the car

p = 190 + c

Mattie drove 120 miles in the same amount of time it took a plane to travel 690 miles

we will use the formula speed = distance/time => time = distance/speed

120/c = 690/p cross multiply

120p = 690c

by solving the system of equations

p = 190 + c

120p = 690c

we find

c = 40 mph

p = 230 mph

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the speed of the plane is 230 mph.