A trapezoid has sides of length 14.3 millimeters, 11.1 millimeters, 14.3 millimeters, and 16.2 millimeters. What is the perimeter?

$${\mathtt{14.3}}{\mathtt{\,\small\textbf+\,}}{\mathtt{11.1}}{\mathtt{\,\small\textbf+\,}}{\mathtt{14.3}}{\mathtt{\,\small\textbf+\,}}{\mathtt{16.2}} = {\frac{{\mathtt{559}}}{{\mathtt{10}}}} = {\mathtt{55.9}}$$

55.9mm

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