we know the trapezoids are similar, so that means all sides are at a ratio, thus

that means from the model to actual, the scale is 1:12, so the large side is 12 times as large.
so for the large trapezoid
EF = 6 * 12 =... 72
EH = 4 * 12 =.. 48
HG = 3 * 12 = ..36
GF = 3 * 12 =...36
72+48+36+36 = 192.