The other two walls are 25.5 x 8, or 204 square feet each.

The total wall area (2*176 + 2*204) is 760 square-feet for the wall area.

Now, subtract 120 for the windows and door, for a final result of 640 square-feet.

At a cost of $2.50 per square foot of plaster, the cost will be $1600.

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A slightly-faster method is to multiply the 8-foot height by the room’s perimeter, which is 22 + 25.5 + 22 + 25.5 = 95 feet.

This also gives an area of 760 square-feet (before subracting 120).

Either way, it’s $1600.

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25.5×8= 204 x 2 = 408 since there are two

760-120= 640ft2

640 x 2.50 = $1600

less 120 = 4368

multiply by $2.50 = $10,920