\(C\%=\dfrac{m_{ct}}{m_{\text{dd}}}.100\%\\ \rightarrow\left\{{}\begin{matrix}m_{ct}=\dfrac{m_{\text{dd}}.C\%}{100}\\m_{\text{dd}}=\dfrac{100.m_{ct}}{C\%}\end{matrix}\right.\\ C_M=\dfrac{n}{V_{dd}}\\ \rightarrow\left\{{}\begin{matrix}n=V_{\text{dd}}.C_M\\V_{\text{dd}}=\dfrac{n}{C_M}\end{matrix}\right.\)