First we need to calculate the areas
The area of a triangle is
[tex]A_T=2\frac{b\times h}{2}=b\times h[/tex]
b=3 in
h=6 in
we substitute the values
[tex]A_T=3\times(6)=18in^2[/tex]
the area combined of the two triangles is 18 in^2
the area of the trapezoid
[tex]A_{Tr}=\frac{(B+b)\cdot h}{2}[/tex]
where
B=12in
b=6in
h=6 in
we substitute the values
[tex]A_{Tr}=\frac{(12+6)\cdot6}{2}=54in^2[/tex]
so the ratio is
54:18
