We need to find the area of the yard. The area can be found as follows:
[tex]A=w\cdot l[/tex]Where:
[tex]\begin{gathered} w=width=50ft=16.67yd \\ l=length=120ft=40yd \end{gathered}[/tex]Therefore, the area is:
[tex]\begin{gathered} A=(16.67)(40) \\ A\approx667yd^2 \end{gathered}[/tex]Answer:
You will need 667 yd² of fertilizer