First we’ll compute the amount of meat necessary to feed every person on earth 110 kilograms per year. In scientific notation, the population of Earth is \(7.8 \times 10^9\) people.
\begin{equation*}
(7.8 \times 10^9 \text{ people}) \times (98.6 \text{ kg/person}) = 7.69 \times 10^{11} \text{ kg meat}
\end{equation*}
Next we’ll compute the amount of grain needed to produce that much meat.
\begin{equation*}
(16 \text{ kg grain/kg meat}) \times (7.69 \times 10^{11} \text{ kg meat}) = 1.23 \times 10^{13} \text{ kg grain}
\end{equation*}
Next we’ll see how many hectares of land are needed to produce that much grain.
\begin{equation*}
(1.23 \times 10^{13} \text{ kg grain}) \div (6000~ \text{ kg grain/hectare}) = 2.05 \times 10^9 \text{ hectares}
\end{equation*}
Finally, we’ll compute the amount of land on Earth suitable for grain production.
\begin{equation*}
0.11 \times (13 \times 10^9 \text{ hectares}) = 1.43 \times 10^9 \text{ hectares}
\end{equation*}
The amount of arable land on Earth is less than the amount needed to produce that much grain. Thus, even if we use every hectare of arable land to produce grain for livestock, we won’t have enough to provide every person on Earth with 98.6 kilograms of meat per year.