Numbers play a significant role in everyone's life. The topic Know Our Numbers deals entirely with the sequence and format of numbers. There are two methods of expressing numbers, namely, the Indian System and the International System. These systems can be used to express numbers both in words and digits. Each number can also be expressed in an expanded notation, which would help calculate a digit's place value.
Various operations like addition, subtraction can be done on the place value of two digits. For example, if the given number is 458965, the place value of the first 5 is 5*1=5 and for the second 5 is 5*10,000=50,000, the product of two-place values is 5*50,000=2,50,000.
The Indian number system varies from the International number system. For example, writing the digits to express a number is slightly different in these two systems, which creates a difference in representing a number in words.
This chapter also discusses the smallest and the largest numbers between the given ranges and how to form 3 or 5 digit numbers using unique digits. In the ascending order, numbers are arranged from lower to higher, whereas the arrangement of numbers is from higher to lower value in the descending order. The chapter Know Our Numbers further gives a glimpse of numbers using simple mathematical operations in real-life situations. Numbers can also be rounded off to the nearest tens, hundreds or even thousands, whenever required. The other way of expressing numbers is with the help of Roman numerals. The Roman method of depicting numbers involves Capital Letters from the English alphabet. The Alphabets in the English language are arranged in particular patterns used to depict numbers; for example, I, II, III, IV, etc., are used to represent the numbers 1, 2, 3, 4, etc. This helps students understand the different writing methods from across the world, making the chapter interesting.