Here;

when we look into the diagram we find the length of the floor area = 18 (We donot need to calculate the area of porch)

Moreover the breadth of the porch = \(4\frac{1}{2}\) ; but we have no information of the length of the porch without which we won't be able to calculate the area of the floor except the porch.

i.e. if we only consider the total floor area i.e length = 18 feet and width = \(18\frac{1}{2}\) {That includes some part of porch area}

Then the area = \(18 * 18\frac{1}{2}\) = 333.

Now we need to subtract the porch area, but we have the breadth but we cannot calculate the length, hence we cannot compute the total area that required painting

Hence the option is E.
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