Weight of 12 books = 4.8 kg
Weight of 1 book = 4.812 kg = 0.4 kg
Weight of 15 books = 0.4 × 15 kg = 6 kg
If the weight of 12 books is 4.8 kg, then the weight of 15 such books will be ___ kg.
The weight of 65 books is 13 kg.(i) What is the weight of 80 such books?(ii) How many such books weigh 6.4 kg?