Let's begin by listing out the information given to us:
[tex]b_1=400ft,h=175ft,b_2=550ft[/tex]
The area of this trapezoid
[tex]\begin{gathered} A=\frac{1}{2}(b_1+b_2)h \\ A=\frac{1}{2}(400+550)\cdot175=\frac{1}{2}(950)\cdot175 \\ A=83125ft^2 \end{gathered}[/tex]
