$1 kg$ of ice at $– 10°C$ is mixed with $4.4 kg$ of water at $30°C$. The final temperature of mixture is 

At $1kg$ ice at $–10°C + 4.4 kg$ of water at $30°C$
Heat gain = Heat loss

$1000\times \frac{1}{2}\times 10+1000\times 80+1000(\mathrm{T}-0)$

$= 4.4\times 1000\times 1\times (30 – T)$

$\Rightarrow 5.4\mathrm{T}=4.4\times 30-85$$\Rightarrow \mathrm{T}=8.7°\mathrm{C}$