A shopkeeper sells wheat at a profit of 10% and uses weight which are 20% less than the actual weight. The total gain earned by him will be?

Let the actual price of per kg of wheat = ₹ . 100
Then, selling price = 110% of 100 = ₹ 110
Now, shopkeeper sell 20% less than actual weight so cost price to shopkeeper will be = 80% of 100
= (80 x 100)/100
= ₹ 80
Hence, required profit gained by shopkeeper = [(110 - 80)/80] x 100
= (30/80) x 100
= 37.5%