A shopkeeper has an unknown weight in his shop. To find out the weight, he first weighs 1 kg of rice and then the unknown weight together. The combined weight of the rice and the unknown weight is 1.5 kg. Find the unknown weight (in grams).
Unknown weight + weight of rice = 1.5kg = 1500 g
weight of rice = 1kg = 1000 g
So, unknown weight = (1500 - 1000)g = 500 g