We can find the answer by using the formula for the area of a trapezoid and putting in the given numbers.
A = (1/2)(b1 +b2)h . . . . where b1, b2 are the base lengths; h is the height
A = (1/2)(198 mi +276 mi)(270 mi)
A = 63,990 mi²
Comment on the area of Missouri
This estimate is about 8.2% low.
The bases are 198 mi and 276 mi. I'm going to say a = 198 mi and b = 276 mi, but you can switch the values of the bases around, it won't affect your solution! The height, h = 270 mi. Plug these values into the equation for the area of a trapezoid and solve for A:
The estimated area of Missouri is .