[tex]\begin{gathered} \text{Investment 1} \\ 12000\cdot0.06=720 \\ 720\text{ interest after 1 year} \\ \text{Investment 2} \\ 5000\cdot0.05=250 \\ 250\text{ interest after 1 year} \\ \text{Combined interest} \\ 720+250=970 \end{gathered}[/tex][tex]\begin{gathered} \text{Divide total interest by total investment} \\ \frac{970}{12000+5000}=\frac{970}{17000}=0.05705882352941176470588235294118 \\ \text{Converted to percent that is} \\ 5.705882352941176470588235294118\% \end{gathered}[/tex]
