The table below shows the carbon content of four samples of powdered coal. If these four samples are mixed completely, what would be the resultant carbon percentage of the mixture by weight?
\begin{array}{|c|c|c|}
\hline Sample number & Mass of sample (kg) & Carbon \% by weight \\
\hline 1 & 2 & 88 \\
\hline 2 & 1 & 90 \\
\hline 3 & 2 & 80 \\
\hline 4 & 1 & 90 \\
\hline
\end{array}
- $58 \%$
- $86 \%$
- $87 \%$
- $90 \%$
