Explanation:
In a 9x9 feet area, an estimate of fifteen people can fit in, which means that
[tex]\begin{gathered} 9\times9=81 \\ \\ 15\text{ per }81\text{ square feet} \end{gathered}[/tex]Calculate the area for 7 feet by 1 mile
[tex]\begin{gathered} \text{Convert 1 mile into feet first} \\ 1\text{ mile }=5280\text{ feet} \\ \\ 7\times5280=36960\text{ square feet} \end{gathered}[/tex]Divide by 81, and multiply by 15
[tex]\begin{gathered} \text{Let }x\text{ be the estimate for the number of people who can fit in} \\ \frac{x}{36960}=\frac{15}{81} \\ x=36960\cdot\frac{15}{81} \\ x=6844.4444 \end{gathered}[/tex]Answer:
Rounding our answer to the nearest whole number, we can estimate that 6844 can stand to watch the school parade.