Class 7 Maths – Large Numbers Around Us Notes

📘 Large Numbers Around Us — Notes

🌍 1. Why Do We Need Large Numbers?

In daily life, we often deal with very big numbers, such as:

  • Population of countries
  • Distance between planets
  • Money in national budgets

Writing these numbers fully can be confusing, so we use place value systems and short forms.


🔢 2. Place Value System (Indian System)

In the Indian system, digits are grouped differently from the international system.

📍 Place Value Chart (Indian System)

PlaceValue
Ones1
Tens10
Hundreds100
Thousands1,000
Ten Thousands10,000
Lakhs1,00,000
Ten Lakhs10,00,000
Crores1,00,00,000

👉 Example:
5,23,45,678 = 5 crore 23 lakh 45 thousand 678


🌐 3. International Place Value System

Used in many countries like the USA.

PlaceValue
Ones1
Thousands1,000
Millions10,00,000
Billions1,000,000,000

👉 Example:
5,23,45,678 (Indian) = 52,345,678 (International)
= 52 million 345 thousand 678


🔁 4. Converting Between Systems

Indian → International

  • Remove Indian commas
  • Place commas after every 3 digits from right

International → Indian

  • First comma after 3 digits from right
  • Then commas after every 2 digits

✍️ 5. Writing Large Numbers in Words

Steps:

  1. Separate periods (crores, lakhs, thousands, etc.)
  2. Write each part in words
  3. Combine them

👉 Example:
7,04,03,210
= Seven crore four lakh three thousand two hundred ten


📊 6. Estimation and Rounding Off

We often approximate numbers to make them easier to use.

Rules:

  • If the next digit is 5 or more → round up
  • If less than 5 → round down

👉 Example:

  • 4,78,213 ≈ 4,80,000 (nearest lakh)
  • 9,432 ≈ 9,000 (nearest thousand)

🧠 7. Comparing Large Numbers

To compare:

  1. Count number of digits
    • More digits → larger number
  2. If equal digits, compare from left

👉 Example:

  • 8,45,321 > 7,99,999
  • 5,67,890 < 5,76,000

🌟 8. Use of Commas

Commas help in reading big numbers easily.

Indian System:

  • 12,34,56,789

International System:

  • 123,456,789

🌌 9. Large Numbers in Real Life

Examples:

  • Population of India → over 140 crore
  • Distance from Earth to Sun → about 150 million km
  • National budgets → in lakhs and crores

📝 10. Key Points to Remember

  • Indian system uses lakhs and crores
  • International system uses millions and billions
  • Always use commas correctly
  • Practice reading and writing numbers in words
  • Estimation helps in quick calculations

✅ Quick Practice

  1. Write in words: 3,45,67,890
  2. Convert to international system: 7,89,45,123
  3. Round off: 6,78,912 to nearest lakh

Large Numbers Around Us – Practice Questions

🔢 Section A: Basic Understanding (1–10)

  1. Write the number name of 4,56,789.
  2. Write in figures: Seven lakh twenty-three thousand five hundred.
  3. How many digits are there in 8,90,12,345?
  4. What is the place value of 7 in 3,47,921?
  5. Write the smallest 6-digit number.
  6. Write the largest 5-digit number.
  7. Expand 6,45,210.
  8. Write 900000 in words.
  9. Identify the digit in the thousands place in 5,67,890.
  10. Write the successor of 9,99,999.

🌍 Section B: Indian & International System (11–20)

  1. Write 45,67,890 in the international system.
  2. Write 23,456,789 in the Indian system.
  3. Express 7,000,000 in Indian system.
  4. Write 5 crore in numbers.
  5. Convert 8 million into Indian system.
  6. Write 9,87,65,432 in international form.
  7. How many lakhs are there in 10 million?
  8. Write 1 billion in Indian system.
  9. Write 6,50,00,000 in words (Indian system).
  10. Write 32,456,789 in words (international system).

🔁 Section C: Place Value & Expansion (21–30)

  1. Find the place value of 5 in 7,54,321.
  2. Write expanded form of 9,08,76,543.
  3. What is the value of 3 in 3,00,45,678?
  4. Write 2,34,56,789 in expanded notation.
  5. Which digit is in the lakh place in 8,76,54,321?
  6. Find the difference between place value and face value of 9 in 9,87,654.
  7. Write the number formed by digits: 5 in lakh place, 3 in thousand place, 7 in ones place.
  8. Write the number when 4 is in crore place and 2 is in thousand place.
  9. Write expanded form of 1,02,03,004.
  10. Identify the digit with highest place value in 7,65,43,210.

📊 Section D: Comparison & Ordering (31–40)

  1. Compare: 5,67,890 ___ 5,76,809
  2. Which is greater: 8,90,123 or 8,09,321?
  3. Arrange in ascending order:
    4,56,789; 4,65,789; 4,56,879
  4. Arrange in descending order:
    9,87,654; 9,78,654; 9,87,645
  5. Which is smallest: 7,65,432; 7,56,432; 7,65,423?
  6. Compare: 10,00,000 ___ 9,99,999
  7. Arrange: 2,34,567; 23,45,678; 2,03,456
  8. Which is greater: 6 million or 60 lakh?
  9. Compare: 1 crore ___ 10 million
  10. Arrange the numbers: 5 crore, 50 lakh, 5000

🔄 Section E: Rounding & Estimation (41–50)

  1. Round 4,56,789 to nearest thousand.
  2. Round 8,76,543 to nearest lakh.
  3. Round 9,99,999 to nearest lakh.
  4. Estimate 5,43,210 to nearest ten thousand.
  5. Round 7,89,456 to nearest thousand.
  6. Round 3,21,678 to nearest lakh.
  7. Estimate 1,49,999 to nearest lakh.
  8. Round 6,50,499 to nearest thousand.
  9. Estimate 2,75,349 to nearest ten thousand.
  10. Round 9,01,234 to nearest lakh.

Answers with Solutions

🔢 Section A: Basic Understanding (1–10)

1. 4,56,789
👉 Four lakh fifty-six thousand seven hundred eighty-nine

2. Seven lakh twenty-three thousand five hundred
👉 7,23,500

3. 8,90,12,345
👉 Total digits = 8

4. Place value of 7 in 3,47,921
👉 7 is in thousand place → 7,000

5. Smallest 6-digit number
👉 1,00,000

6. Largest 5-digit number
👉 99,999

7. 6,45,210 (Expanded form)
👉 6,00,000 + 40,000 + 5,000 + 200 + 10

8. 900000 in words
👉 Nine lakh

9. Thousands place in 5,67,890
👉 Digit = 7

10. Successor of 9,99,999
👉 10,00,000


🌍 Section B: Indian & International System (11–20)

11. 45,67,890
👉 4,567,890

12. 23,456,789
👉 2,34,56,789

13. 7,000,000
👉 70,00,000

14. 5 crore
👉 5,00,00,000

15. 8 million
👉 80,00,000

16. 9,87,65,432
👉 98,765,432

17. 10 million
👉 100 lakh

18. 1 billion
👉 100 crore

19. 6,50,00,000
👉 Six crore fifty lakh

20. 32,456,789
👉 Thirty-two million four hundred fifty-six thousand seven hundred eighty-nine


🔁 Section C: Place Value & Expansion (21–30)

21. 5 in 7,54,321
👉 5 is in ten-thousand place → 50,000

22. 9,08,76,543
👉 9,00,00,000 + 8,00,000 + 70,000 + 6,000 + 500 + 40 + 3

23. Value of 3 in 3,00,45,678
👉 Crore place → 3,00,00,000

24. 2,34,56,789
👉 2,00,00,000 + 30,00,000 + 4,00,000 + 50,000 + 6,000 + 700 + 80 + 9

25. Lakh place in 8,76,54,321
👉 Digit = 6

26. Face value = 9
Place value = 9,00,000
👉 Difference = 8,99,991

27. Number formation
👉 5 lakh + 3 thousand + 7 = 5,03,007

28. 4 in crore place, 2 in thousand
👉 4,00,02,000

29. 1,02,03,004
👉 1,00,00,000 + 2,00,000 + 3,000 + 4

30. Highest place value in 7,65,43,210
👉 Digit 7 (crore place)


📊 Section D: Comparison & Ordering (31–40)

31. 5,67,890 < 5,76,809

32. 8,90,123 > 8,09,321

33. Ascending:
👉 4,56,789 < 4,56,879 < 4,65,789

34. Descending:
👉 9,87,654 > 9,87,645 > 9,78,654

35. Smallest:
👉 7,56,432

36. 10,00,000 > 9,99,999

37. Ascending:
👉 2,03,456 < 2,34,567 < 23,45,678

38. 6 million = 60 lakh
👉 Equal

39. 1 crore = 10 million
👉 Equal

40. Ascending:
👉 5000 < 50 lakh < 5 crore


🔄 Section E: Rounding & Estimation (41–50)

41. 4,56,789 ≈ 4,57,000 (nearest thousand)

42. 8,76,543 ≈ 9,00,000 (nearest lakh)

43. 9,99,999 ≈ 10,00,000

44. 5,43,210 ≈ 5,40,000

45. 7,89,456 ≈ 7,89,000

46. 3,21,678 ≈ 3,00,000

47. 1,49,999 ≈ 1,00,000

48. 6,50,499 ≈ 6,50,000

49. 2,75,349 ≈ 2,80,000

50. 9,01,234 ≈ 9,00,000