Given data: Mass of ice, $m_1 = 15\text{ g} = 0.015\text{ kg}$ Initial temperature of ice, $\theta_1 = 0^\circ\text{C}$ Mass of water, $m_2 = 60\text{ g} = 0.06\text{ kg}$ Initial temperature of water, $\theta_2 = 60^\circ\text{C}$ Latent heat of fusion of ice, $L_f = 336000\text{ J/kg}$ Specific heat capacity of water, $s = 4200\text{ J/(kg}\cdot\text{K)}$ Let the final temperature of the mixture be $\theta$. According to the principle of calorimetry, the heat gained by the ice to melt and reach the final temperature equals the heat lost by the water to reach the final temperature: $$ \begin{aligned} Q_{\text{gained}} &= Q_{\text{lost}} \\ m_1 L_f + m_1 s (\theta - \theta_1) &= m_2 s (\theta_2 - \theta) \end{aligned} $$ Substituting the values: $$ \begin{aligned} (0.015 \times 336000) + (0.015 \times 4200 \times (\theta - 0)) &= 0.06 \times 4200 \times (60 - \theta) \\ 5040 + 63\theta &= 252 \times (60 - \theta) \\ 5040 + 63\theta &= 15120 - 252\theta \\ 63\theta + 252\theta &= 15120 - 5040 \\ 315\theta &= 10080 \\ \theta &= \frac{10080}{315} \\ \theta &= 32 \end{aligned} $$ Therefore, the final temperature of the mixture is $32^\circ\text{C}$.