​​solve it

Hi Prince,

(1)
$$\begin{gathered} \mathrm{Let} \mathrm{cost} \mathrm{be} \text{'}x\text{'} \\ \mathrm{Sales} = .25x+x \\ 7,50,000=1.25x \\ x=6,00,000 \left(\mathrm{COGS}\right) \\ \mathrm{COGS}=\mathrm{Opening} \mathrm{Stock}+\mathrm{Purchases}-\mathrm{Closing} \mathrm{Stock} \\ \mathrm{Let} \mathrm{Opening} \mathrm{Stock} \mathrm{be} \text{'}x\text{'} \\ \mathrm{Closing} \mathrm{Stock}=1.5x \\ 6,00,000=x+6,50,000-1.5x \\ x=\mathrm{Rs} 1,00,000 (\mathrm{Opening} \mathrm{Stock}) \\ \mathrm{Closing} \mathrm{Stock}=1,50,000 (1.5\times 1,00,000) \end{gathered}$$

(2)
$$\begin{gathered} \mathrm{Gross} \mathrm{Profit}=3,00,000 (20\% \mathrm{of} \mathrm{sales}) \\ \mathrm{Gross} \mathrm{Profit}=25\% \mathrm{on} \mathrm{cost} \\ \mathrm{Let} \mathrm{cost} \mathrm{be} \text{'}x\text{'} \\ 3,00,000=\frac{25}{100}\times x \\ x=12,00,000 \left(\mathrm{COGS}\right) \end{gathered}$$

(3)
$$\begin{gathered} \mathrm{Gross} \mathrm{Profit}=25\% \mathrm{on} \mathrm{sales} (\mathrm{or} \frac{1}{3}\mathrm{on} \mathrm{cost}) \\ \mathrm{Gross} \mathrm{Profit}=\frac{1}{3}\times 6,00,000=\mathrm{Rs} 2,00,000 \\ \mathrm{Let} \mathrm{sales} \mathrm{be} \text{'}x\text{'} \\ 2,00,000=\frac{1}{4}\times x \\ x=8,00,000 \end{gathered}$$

(4)
$$\begin{gathered} \mathrm{Gross} \mathrm{Profit}=25\% \mathrm{on} \mathrm{cost} (\mathrm{or} \frac{1}{5}\mathrm{on} \mathrm{sale}) \\ \mathrm{Gross} \mathrm{Profit}=\frac{1}{5}\times 4,00,000=\mathrm{Rs} 80,000 \\ \mathrm{COGS}=\mathrm{Sales}-\mathrm{Gross} \mathrm{Profit} \\ =4,00,000-80,000=\mathrm{Rs} 3,20,000 \\ \mathrm{COGS}=\mathrm{Opening} \mathrm{Stock}+\mathrm{Purchases}-\mathrm{Closing} \mathrm{Stock} \\ \mathrm{Let} \mathrm{Opening} \mathrm{Stock} \mathrm{be} \text{'}x\text{'} \\ \mathrm{Closing} \mathrm{Stock}=20,000+x \\ 3,20,000=x+\mathrm{Purchases}+20,000+x \\ 3,20,000=2x+20,000+\mathrm{Purchases} \\ \mathrm{Purchases}=3,00,000-2x \\ \mathrm{Note}: \mathrm{This} \mathrm{question} \mathrm{cannot} \mathrm{be} \mathrm{solved} \mathrm{further}. \end{gathered}$$

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