Answer: Approximately 9.33 square units
As a fraction, this is exactly 28/3
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Explanation:
Let's say the height of the upper-left smallest rectangle (area 6) has height of 2. This height doesn't matter and can be anything you want, and it won't affect the final answer.
This means its horizontal portion of area 6 is 6/2 = 3 units across.
The horizontal portion of 3 corresponds directly to the horizontal part of the lower left rectangle (area 7) as well. The height of this rectangle is 7/3. We'll come back to this later.
Since the height of area 6 is 2 units, this also the height of area 8. The horizontal portion of area 8 must be 8/2 = 4 units.
Since the horizontal portion of area 8 is 4 units, and the vertical portion of area 7 is 7/3, this makes the area we're after to be 4*(7/3) = 28/3 = 9.33 approximately.
