



 
Hi Rebecca, The area of a circle is $\pi$ times the diameter where $\pi$ is approximately 3.1416. A semicircle is half a circle so the area of a semicircle is $\large \frac12 \times \pi$ times the diameter. The two areas, that of the semicircle and the rectangle, are numbers so to add the areas just add the numbers. I hope this helps,  


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