Explanation:

- Gross Profit is calculated as: Revenue - Cost of Goods Sold (COGS).

- COGS includes the Opening Inventory, Purchases, Wages, Carriage Inwards, minus Closing Inventory.

- Formula Calculation:

$$ \text{COGS} = \text{Opening Inventory} + \text{Purchases} + \text{Wages} + \text{Carriage Inwards} - \text{Closing Inventory} $$

$$ = 1,00,000 + 20,00,000 + 2,40,000 + 1,50,000 - 1,20,000 = 23,70,000 $$

- Gross Profit = Revenue - COGS = 30,00,000 - 23,70,000 = 6,30,000

- Gross Profit Ratio = (Gross Profit / Revenue) x 100

- $$ \text{Gross Profit Ratio} = (6,30,000 / 30,00,000) \times 100 = 21\% $$

- Option 1: 29%

- Option 2: 26%

- Option 3: 19%

- Option 4: 21%