The cost of painting the rectangular board with a semicircular top is $31.065 to the nearest hundredth.
<h3>How to find the area of the composite figures?</h3>
To find area of the composite figures,
- Separate the figure.
- Calculate the are of the each figure by which the composite figure is made of.
- Add the area of all the individual figures to get the total area of composite figures.
The dimentions of the rectangle is 3 by 4 foot. The area of the rectangle is,

The radius of the semicircle is 1.5 m. The area of the semicircle is,

The area of the composite figure is,

The rate of painting is $2.00 per square foot. Thus the cost to paint the figure is,
Hence, the cost of painting the rectangular board with a semicircular top is $31.065 to the nearest hundredth.
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