### Mathematics for Class 5

**NUMBERS AND ARITHMETIC OPERATIONS**

**(Numbers up to one billion)**

**1.1 Numbers up to one billion**

Read numbers up to one billion in numerals and in words

**Concept of One Billion**

We have learnt in Class IV that the smallest number of nine digits is 100000000 (one hundred million).

**Look at the number "34,768,172"**

- How many millions are in
**34,768,172** - How many thousands are in
**34,768,172** - How many ones are in
**34,768,172** - Write
**34,768,172**in words.

We know that the greatest number of nine digits is 999,999,999 read as "Nine hundred ninety nine millions, nine hundred ninety nine thousands and nine hundred ninety nine". When we add one more to it, then

999,999,999 + 1 = 1,000,000,000

**Teacher's Note:** After revision of numbers in millions, teacher should help students to develop the concept of one billion by counting numbers of digits by using flash cards or other related material.