Invoice Details:
- Invoice No: 2007
- Sold to: M/s Garry Sons, Delhi
- Quantity: 50 Kg Assam Tea
- Rate: Rs. 600 per Kg
- Trade Discount: 5%
- IGST: 12%
- Freight and Packing Charges: Rs. 1,600

Calculating the IGST:
Step 1: Calculate the Total Amount before Trade Discount
- Quantity: 50 Kg
- Rate: Rs. 600 per Kg
- Total Amount before Trade Discount = Quantity * Rate
= 50 Kg * Rs. 600 per Kg
= Rs. 30,000

Step 2: Calculate the Trade Discount
- Trade Discount: 5%
- Trade Discount Amount = Total Amount before Trade Discount * Trade Discount / 100
= Rs. 30,000 * 5 / 100
= Rs. 1,500

Step 3: Calculate the Total Amount after Trade Discount
- Total Amount after Trade Discount = Total Amount before Trade Discount - Trade Discount Amount
= Rs. 30,000 - Rs. 1,500
= Rs. 28,500

Step 4: Calculate the IGST Amount
- IGST: 12%
- IGST Amount = Total Amount after Trade Discount * IGST / 100
= Rs. 28,500 * 12 / 100
= Rs. 3,420

Final Invoice Calculation:
- Total Amount before Trade Discount: Rs. 30,000
- Trade Discount: Rs. 1,500
- Total Amount after Trade Discount: Rs. 28,500
- IGST Amount: Rs. 3,420
- Freight and Packing Charges: Rs. 1,600

The final invoice will include:
- Total Amount after Trade Discount: Rs. 28,500
- IGST Amount: Rs. 3,420
- Freight and Packing Charges: Rs. 1,600

Summary:
- The total amount before trade discount was calculated by multiplying the quantity of tea (50 Kg) by the rate per Kg (Rs. 600).
- The trade discount was applied at 5% on the total amount before the discount.
- The total amount after the trade discount was calculated by subtracting the trade discount amount from the total amount before the discount.
- The IGST amount was calculated by applying the IGST rate (12%) on the total amount after the trade discount.
- The freight and packing charges (Rs. 1,600) were separately charged in the invoice.
- The final invoice included the total amount after the trade discount, the IGST amount, and the freight and packing charges.