First find the area of the whole square. Even the part that isn't part of the area. Then find the area of the spots that aren't part of the shape. Then subtract that area from the area of the whole thing.
15×18=270
(9x12)+(4×5)=128
270-128=142
Area= 142ft^2
The volume (V) is given in terms of length (L), width (W), and height (H) by the formula ...
... V = LWH
Substituting your dimensions, you have
... V = (11.3 cm)·(18.9 cm)·(29 cm) = 6193.53 cm³ ≈ 6200 cm³
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The factor 29 cm has 2 significant digits, so that is the precision required of the answer. It could also be written with less ambiguity as to precision as 6.2 L. (Trailing zeros to the left of the decimal point are always ambiguous when it comes to significant digits.)
1/4= 0.25
2/4= 1/2 = 0.5
0.25 x 0.5 = 0.125
0.125 = 1/8
