What is the gross sales for this problem ?? please help ..

Gross Sales = 13,90,000

Here's how it is solved:

GP is 20% on sales that means 25% of cost of goods sold

COGS = Op. Stock + (Purchase - return outwards) + Carriage Inwards - Closing Stock

COGS = 60000 + 1120000 - 30000 + 10000 -80000

COGS = 1080000

GP = 1080000 * 0.25

GP = 270000

Since GP is 20% of net sales

Net sales = 270000/20%

Net Sales = 1350000

Gross Sales = Net Sales + Return Inwards

Gross Sales = 1350000 + 40000

Gross Sales = 1390000