An alloy contains the copper and aluminum in the ratio 7:4. While making the weapons from this alloy, 12% of the alloy get destroyed. If there are 12 kg of aluminum in the weapon, then the weight of the alloy required is :
48 kg
40 kg
37.5 kg
14.4 kg
Copper : aluminum = 7:4
$\begin{aligned} & (88 / 100) *(4 \mathrm{x} / 11)=12 \\ & \mathrm{X}=37.5 \mathrm{~kg}\end{aligned}$