Answer:
- Add 75 for the blank number
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Divide the figure by three parts for easy calculation of its area:
- Rectangle of 5 by 10 units,
- Square of 5 units,
- Quarter-circle of 5 units radius.
Find each area and add up:
- A = 5*10 + 5*5 + π*5²/4
- A = 50 + 25 + 25π/4
- A = 75 + 25π/4
The blank is 75.