5 kg of metal A and 20 kg of metal B are mixed to form an alloy. The percentage of metal A in the alloy is ?

Answer: Option A

Weight of metal A = 5kg
Total weight of the alloy :
= (5 + 20) kg
= 25 kg
∴ Required percentage :
$$\begin{array}{rl}& =\left(\frac{5}{25}\times 100\right)\%\\ & =20\%\end{array}$$