Kilograms and grams

In your book, Maths Mela (Chapter 8), bags are weighed on two balances. One shows kilograms and the other shows grams. A 2 kg bag shows 2,000 g, because 1 kg = 1,000 g. So 3 kg = 3,000 g, 5 kg = 5,000 g, and 25 kg = 25,000 g: to change kg into g, multiply by 1,000.

Shrenu is baking cakes and needs 3 kg 500 g of flour, but her kitchen scale shows only grams. 3 kg is 3,000 g, and 500 g more makes 3,500 g. In the same way, 2 kg 250 g = 2,000 g + 250 g = 2,250 g.

Shamim and Rehan see someone buying 5 kg 50 g of sugar. One of them says it is 5,050 g; the other says it is 5,500 g. 5 kg is 5,000 g, and 50 g more is 5,050 g. The answer 5,500 g would be 5 kg 500 g, which is 450 g too much. Be careful with the grams: 50 g, 500 g and 5 g are all different.

We can go the other way too. 10,760 g is 10,000 g and 760 g, so it is 10 kg 760 g. 4,080 g is 4 kg 80 g. The digits before the comma give the kilograms, and the last three digits give the grams.

Harpreet's family takes fruit on a picnic: watermelon 3 kg, pineapple 1 kg 750 g, apples 1 kg 250 g and mangoes 2 kg. To compare, look at the kilograms first. The watermelon has the most kilograms, so it is the heaviest. The pineapple and the apples both have 1 kg, so compare their grams: 750 g is more than 250 g. So the apples are the lightest. In descending order (heaviest first): watermelon, mangoes, pineapple, apples. When units are mixed, change both to grams: 1 kg 600 g is 1,600 g, which is less than 1,700 g.