Class 7 : Maths – Lesson 1. Large Numbers Around Us

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On December 11, 2025

EXPLANATION AND ANALYSIS

🔵 Introduction: Large Numbers in Everyday Life

🧠 In our daily activities, we usually deal with small numbers such as the number of books, students, or money spent on simple items. However, there are many situations around us where numbers become very large. Such numbers appear when we read newspapers, watch news, or study subjects like science and geography.

🌿 Examples from daily life
🔵 Population of a country is counted in crores
🟢 Distance between planets is measured in thousands or lakhs of kilometres
🟡 Government budgets involve very large numbers
🔴 Digital data is measured in gigabytes and terabytes

➡️ To understand these facts clearly, we must learn how to read, write, compare, and estimate large numbers correctly. This chapter introduces these ideas.

🟢 Place Value: The Basis of Large Numbers

🧠 Every digit in a number has a value depending on its position. This is called the place value of the digit.

📌 Example
In the number 4,36,728, the digit 3 represents 30,000.

💡 Concept:
Each place to the left has a value ten times greater than the place to its right.

🔵 Indian Place Value System

🧠 In India, we follow the Indian place value system.

🔵 Ones
🟢 Tens
🟡 Hundreds
🔴 Thousands
🔵 Lakhs
🟢 Crores

📌 Example
The number 6,48,25,309 is read as
Six crore forty-eight lakh twenty-five thousand three hundred nine

✏️ Note:
In the Indian system, commas are placed after the first three digits from the right and then after every two digits.

🟢 International Place Value System

🌍 Many other countries use the International place value system.

🔵 Ones
🟢 Tens
🟡 Hundreds
🔴 Thousands
🔵 Millions
🟢 Billions

📌 Example
The number 64,825,309 is read as
Sixty-four million eight hundred twenty-five thousand three hundred nine

💡 Concept:
Indian system uses lakh and crore, while International system uses million and billion.

🟡 Reading Large Numbers

🧠 To read large numbers correctly, we should follow a fixed method.

🔵 Place commas correctly
🟢 Start reading from the leftmost group
🟡 Use correct place value names

📌 Example
5,03,07,418 is read as
Five crore three lakh seven thousand four hundred eighteen

🔴 Common mistake:
Reading digits one by one instead of using place values.

🔵 Writing Large Numbers in Numerals

🧠 While writing numbers given in words, it is important to identify place value words like thousand, lakh, and crore.

📌 Example
Seven crore four lakh two thousand sixty-five
7,04,02,065

✏️ Note:
Zeros are very important in large numbers. Missing a zero changes the value of the number.

🟢 Comparing Large Numbers

🧠 Large numbers can be compared easily by following a fixed order.

🔵 Step 1: Compare the number of digits
🟢 Step 2: If digits are equal, compare digits from the left
🟡 Step 3: The number with the greater digit is larger

📌 Example
Compare 8,34,912 and 8,29,745
Both have six digits
At the ten-thousands place, 3 is greater than 2
So 8,34,912 is greater

🟡 Ordering Large Numbers

🧠 Ordering means arranging numbers in a particular sequence.

🔵 Ascending order means smallest to greatest
🟢 Descending order means greatest to smallest

📌 Example
2,84,679, 2,96,540, 3,10,428 in ascending order
2,84,679 < 2,96,540 < 3,10,428

🔵 Estimation and Rounding Off

🧠 Estimation gives an approximate value of a number when an exact value is not required.

🔵 Look at the digit to the right
🟢 If it is less than 5, round down
🟡 If it is 5 or more, round up

📌 Example
Round 6,72,418 to the nearest thousand
The hundreds digit is 4
The rounded value is 6,72,000

💡 Concept:
Estimation makes calculations quicker and easier.

🟢 Use of Large Numbers in Daily Life

🌿 Large numbers are used in many fields.

🔵 Population studies
🟢 Space science
🟡 Banking and finance
🔴 Government planning
🔵 Digital storage

📌 Example
The distance between Earth and the Moon is about 3,84,400 kilometres.

🔴 Common Errors to Avoid

🔴 Wrong placement of commas
🔴 Mixing Indian and International systems
🔴 Forgetting zeros
🔴 Incorrect reading of place values

✏️ Note:
Always recheck comma placement before reading or writing a number.

🟢 Importance of Learning Large Numbers

🧠 Understanding large numbers helps us interpret real-world data correctly.

🔵 Builds strong number sense
🟢 Helps in science and geography
🟡 Useful for higher mathematics
🔴 Important for everyday understanding

📘 Summary

🔵 Large numbers help us describe very big quantities
🟢 Place value gives meaning to each digit
🟡 Indian and International systems are different
🔴 Correct reading and writing depend on comma placement
🔵 Numbers can be compared and ordered easily
🟢 Estimation gives approximate values
🟡 Large numbers are used widely in daily life

📝 Quick Recap

📝 Quick Recap
🔵 Large numbers represent huge quantities
🟢 Place value decides digit value
🟡 Indian system uses lakh and crore
🔴 International system uses million and billion
🔵 Estimation simplifies calculations

——————————————————————————————————————————————————————————————————————————–

TEXTBOOK QUESTIONS

🌿 1.1 A LAKH VARIETIES!

🔒 ❓ Question 1.
According to the 2011 Census, the population of the town of Chintamani was about 75,000. How much less than one lakh is 75,000?

📌 ✅ Answer:
🔹 One lakh = 1,00,000
🔹 Given population = 75,000
🔹 Difference = 1,00,000 − 75,000
🔸 = 25,000

✔️ Final: 75,000 is 25,000 less than one lakh.

🔒 ❓ Question 2.
The estimated population of Chintamani in the year 2024 is 1,06,000. How much more than one lakh is 1,06,000?

📌 ✅ Answer:
🔹 One lakh = 1,00,000
🔹 Estimated population = 1,06,000
🔹 Difference = 1,06,000 − 1,00,000
🔸 = 6,000

✔️ Final: 1,06,000 is 6,000 more than one lakh.

🔒 ❓ Question 3.
By how much did the population of Chintamani increase from 2011 to 2024?

📌 ✅ Answer:
🔹 Population in 2011 = 75,000
🔹 Population in 2024 = 1,06,000
🔹 Increase = 1,06,000 − 75,000
🔸 = 31,000

✔️ Final: The population increased by 31,000 from 2011 to 2024.

🌿 1.2 LAND OF TENS

🔒 ❓ Figure it Out (a)
For the number 8300, write expressions for at least two different ways to obtain the number through button clicks.

📌 ✅ Answer:
🔹 Way 1: (83 × 100) = 8300
🔹 Way 2: (8 × 1000) + (3 × 100) = 8300

🔒 ❓ Figure it Out (b)
For the number 40629, write expressions for at least two different ways to obtain the number through button clicks.

📌 ✅ Answer:
🔹 Way 1: (40 × 1000) + (6 × 100) + (2 × 10) + (9 × 1) = 40629
🔹 Way 2: (4 × 10000) + (62 × 10) + (9 × 1) = 40629

🔒 ❓ Figure it Out (c)
For the number 56354, write expressions for at least two different ways to obtain the number through button clicks.

📌 ✅ Answer:
🔹 Way 1: (56 × 1000) + (3 × 100) + (5 × 10) + (4 × 1) = 56354
🔹 Way 2: (5 × 10000) + (63 × 100) + (5 × 10) + (4 × 1) = 56354

🔒 ❓ Figure it Out (d)
For the number 66666, write expressions for at least two different ways to obtain the number through button clicks.

📌 ✅ Answer:
🔹 Way 1: (6 × 10000) + (6 × 1000) + (6 × 100) + (6 × 10) + (6 × 1) = 66666
🔹 Way 2: (66 × 1000) + (6 × 100) + (6 × 10) + (6 × 1) = 66666

🔒 ❓ Figure it Out (e)
For the number 367813, write expressions for at least two different ways to obtain the number through button clicks.

📌 ✅ Answer:
🔹 Way 1: (3 × 100000) + (6 × 10000) + (7 × 1000) + (8 × 100) + (1 × 10) + (3 × 1) = 367813
🔹 Way 2: (367 × 1000) + (8 × 100) + (1 × 10) + (3 × 1) = 367813

🔒 ❓ Question 1.
For the numbers in the previous exercise, find out how to get each number by making the smallest number of button clicks and write the expression.

📌 ✅ Answer:
🔹 8300
🔸 (8 × 1000) + (3 × 100) = 8300

🔹 40629
🔸 (4 × 10000) + (0 × 1000) + (6 × 100) + (2 × 10) + (9 × 1) = 40629

🔹 56354
🔸 (5 × 10000) + (6 × 1000) + (3 × 100) + (5 × 10) + (4 × 1) = 56354

🔹 66666
🔸 (6 × 10000) + (6 × 1000) + (6 × 100) + (6 × 10) + (6 × 1) = 66666

🔹 367813
🔸 (3 × 100000) + (6 × 10000) + (7 × 1000) + (8 × 100) + (1 × 10) + (3 × 1) = 367813

🔒 ❓ Question 2.
Do you see any connection between each number and the corresponding smallest number of button clicks?

📌 ✅ Answer:
🔹 The smallest number of button clicks is obtained by using the place value of each digit.
🔹 Each digit tells how many times a particular place-value button is pressed.
🔹 This avoids unnecessary extra button presses and gives the minimum total clicks.

🔒 ❓ Question 3.
If you notice, the expressions for the least button clicks also give the Indian place value notation of the numbers. Think about why this is so.

📌 ✅ Answer:
🔹 Indian place value notation breaks a number into digits multiplied by their place values.
🔹 Creative Chitti’s buttons exactly match these place values (+1, +10, +100, +1000, …).
🔹 Therefore, using the least button clicks naturally follows the Indian place value system.

🌿 1.3 OF CRORES AND CRORES!

🔒 ❓ Question 1.
Read the following numbers in Indian place value notation and write their number names in both the Indian and American systems.

📌 ✅ Answer:
🔹 (a) 4050678
🔸 Indian system: Forty lakh fifty thousand six hundred seventy eight
🔸 American system: Four million fifty thousand six hundred seventy eight

🔹 (b) 48121620
🔸 Indian system: Four crore eighty one lakh twenty one thousand six hundred twenty
🔸 American system: Forty eight million one hundred twenty one thousand six hundred twenty

🔹 (c) 20022002
🔸 Indian system: Two crore two thousand two
🔸 American system: Twenty million twenty two thousand two

🔹 (d) 246813579
🔸 Indian system: Twenty four crore sixty eight lakh thirteen thousand five hundred seventy nine
🔸 American system: Two hundred forty six million eight hundred thirteen thousand five hundred seventy nine

🔹 (e) 345000543
🔸 Indian system: Thirty four crore fifty lakh five hundred forty three
🔸 American system: Three hundred forty five million five hundred forty three

🔹 (f) 1020304050
🔸 Indian system: One hundred two crore three lakh four thousand fifty
🔸 American system: One billion twenty million three hundred four thousand fifty

🔒 ❓ Question 2.
Write the following numbers in Indian place value notation.

📌 ✅ Answer:
🔹 (a) One crore one lakh one thousand ten
🔸 1,01,01,010

🔹 (b) One billion one million one thousand one
🔸 1,00,10,01,001

🔹 (c) Ten crore twenty lakh thirty thousand forty
🔸 10,20,30,040

🔹 (d) Nine billion eighty million seven hundred thousand six hundred
🔸 90,80,07,00,600

🔒 ❓ Question 3.
Compare and write ‘<’, ‘>’ or ‘=’.

📌 ✅ Answer:
🔹 (a) 30 thousand < 3 lakhs
🔹 (b) 500 lakhs = 5 million
🔹 (c) 800 thousand < 8 million
🔹 (d) 640 crore > 60 billion

🌿 1.5 PATTERNS IN PRODUCTS

🔒 ❓ Figure it Out — Question 1
Find quick ways to calculate these products.

📌 ✅ Answer:
🔹 (a) 2 × 1768 × 50
🔸 (2 × 50) × 1768 = 100 × 1768 = 176800

🔹 (b) 72 × 125
🔸 125 = 1000 / 8
🔸 72 × (1000 / 8) = 9 × 1000 = 9000

🔹 (c) 125 × 40 × 8 × 25
🔸 (125 × 8) × (40 × 25)
🔸 1000 × 1000 = 1000000

🔒 ❓ Figure it Out — Question 2
Calculate these products quickly.

📌 ✅ Answer:
🔹 (a) 25 × 12
🔸 (100 / 4) × 12 = 300
✔️ Final: 300

🔹 (b) 25 × 240
🔸 (100 / 4) × 240 = 6000
✔️ Final: 6000

🔹 (c) 250 × 120
🔸 (1000 / 4) × 120 = 30000
✔️ Final: 30000

🔹 (d) 2500 × 12
🔸 (10000 / 4) × 12 = 30000
✔️ Final: 30000

🔹 (e) _____ × _____ = 12000000
🔸 12000 × 1000 = 12000000

🌿 1.6 DID YOU EVER WONDER…?

🔒 ❓ Question 1
Using all digits from 0–9 exactly once (the first digit cannot be 0) to create a 10-digit number, write the—
(a) Largest multiple of 5
(b) Smallest even number

📌 ✅ Answer:

🔹 (a) Largest multiple of 5
🔸 A multiple of 5 must end in 0 or 5.
🔸 To make the number largest, place the largest digits in the highest places.
🔸 Ending with 0 gives a larger number than ending with 5.
🔸 Arrange remaining digits from 9 to 1 in descending order.

✔️ Final: 9876543210

🔹 (b) Smallest even number
Smallest even number

📌 ✅ Answer:
🔹 The number must use digits 0–9 exactly once, and the first digit cannot be 0.
🔹 To make it smallest, keep the smallest digits as early as possible: start with 1, then 0, then 2, 3, 4, 5, 6, 7.
🔹 The last digit must be even, so place 8 at the end and keep 9 just before it.

📌 ✅ Final: 1023456798

🔒 ❓ Question 2
The number 10,30,285 in words is Ten lakhs thirty thousand two hundred eighty five, which has 43 letters. Give a 7-digit number name which has the maximum number of letters.

📌 ✅ Answer:

🔹 Comparing long 7-digit number names shows that the word “seventy” (7 letters) repeated many times gives more letters than “ninety” (6 letters).
🔹 The number 7,777,777 uses seventy and seven repeatedly along with lakh, thousand, and hundred, making its name very long.

🔹 In words (Indian system):
Seventy seven lakh seventy seven thousand seven hundred seventy seven

📌 ✅ Final: 7,777,777

🔒 ❓ Question 3
Write a 9-digit number where exchanging any two digits results in a bigger number. How many such numbers exist?

📌 ✅ Answer:

🔹 For the number to increase after any exchange, the original number must be:
🔸 Arranged in strictly increasing order from left to right.

🔹 Smallest digits on the left, largest on the right.

🔹 Example:
🔸 123456789

🔹 Any swap will move a larger digit to a higher place value, making the number larger.

🔹 Count of such numbers:
🔸 Only one such arrangement is possible using digits 1–9 once.

✔️ Final:
🔹 Number: 123456789
🔹 Total such numbers: 1

🔒 ❓ Question 4
Strike out 10 digits from the number 12345123451234512345 so that the remaining number is as large as possible.

📌 ✅ Answer:
🔹 We must delete 10 digits and keep 10 digits in the same order (a subsequence).
🔹 To maximize the remaining 10-digit number, keep the earliest possible high digits (5s), while still leaving enough digits to complete 10 places.
🔹 The largest possible remaining 10-digit number is obtained by keeping digits that form:

📌 ✅ Final: 5534512345

🔒 ❓ Question 5
The words ‘zero’ and ‘one’ share letters ‘e’ and ‘o’. The words ‘one’ and ‘two’ share a letter ‘o’, and the words ‘two’ and ‘three’ also share a letter ‘t’. How far do you have to count to find two consecutive numbers which do not share an English letter in common?

📌 ✅ Answer:
🔹 Checking consecutive number-names in standard English spelling shows that every consecutive pair shares at least one common letter.
🔹 This overlap continues because the same letters keep recurring in number words across ones, tens, hundreds, thousands, etc.

✔️ Final: You cannot find such a pair of consecutive numbers (so there is no finite counting point where this happens).

🔒 ❓ Question 6
Suppose you write down all the numbers 1, 2, 3, 4, …, 9, 10, 11, …
The tenth digit you write is ‘1’ and the eleventh digit is ‘0’, as part of the number 10.

(a) What would the 1000th digit be? At which number would it occur?
(b) What number would contain the millionth digit?
(c) When would you have written the digit ‘5’ for the 5000th time?

📌 ✅ Answer:

🔹 (a) 1000th digit
🔸 Digits from 1 to 9 = 9
🔸 Digits from 10 to 99 = 90 × 2 = 180
🔸 Total digits up to 99 = 9 + 180 = 189
🔸 Position inside 3-digit numbers = 1000 − 189 = 811
🔸 Each 3-digit number gives 3 digits
🔸 Number offset = (811 − 1) ÷ 3 = 270
🔸 Digit position inside the number = (811 − 1) mod 3 = 0 (first digit)
🔸 Number = 100 + 270 = 370
🔸 First digit of 370 = 3

✔️ Final: 1000th digit is 3, and it occurs in the number 370

🔹 (b) millionth digit
🔸 Digits up to 9 = 9
🔸 Digits from 10 to 99 = 180
🔸 Digits from 100 to 999 = 900 × 3 = 2700
🔸 Total up to 999 = 9 + 180 + 2700 = 2889
🔸 Digits from 1000 to 9999 = 9000 × 4 = 36000
🔸 Total up to 9999 = 2889 + 36000 = 38889
🔸 Digits from 10000 to 99999 = 90000 × 5 = 450000
🔸 Total up to 99999 = 38889 + 450000 = 488889
🔸 Millionth position inside 6-digit numbers = 1000000 − 488889 = 511111
🔸 Each 6-digit number gives 6 digits
🔸 Number offset = (511111 − 1) ÷ 6 = 85185
🔸 Number = 100000 + 85185 = 185185

✔️ Final: The millionth digit is contained in the number 185185

🔹 (c) digit ‘5’ for the 5000th time

📌 ✅ Answer:
🔹 Count of digit ‘5’ written from 1 up to 13494 is 4999.
🔹 The next number 13495 adds one more ‘5’, making the total 5000.

✔️ Final: The digit ‘5’ is written for the 5000th time while writing the number 13495.

🔒 ❓ Question 7
A calculator has only ‘+10,000’ and ‘+100’ buttons. Write an expression describing the number of button clicks to be made for the following numbers:

(a) 20,800
(b) 92,100
(c) 1,20,500
(d) 65,30,000
(e) 70,25,700

📌 ✅ Answer:

🔹 (a) 20,800
🔸 2 × 10,000 = 20,000
🔸 8 × 100 = 800
🔸 20,000 + 800 = 20,800
📌 ✅ Final: 2 clicks of +10,000 and 8 clicks of +100

🔹 (b) 92,100
🔸 9 × 10,000 = 90,000
🔸 21 × 100 = 2,100
🔸 90,000 + 2,100 = 92,100
📌 ✅ Final: 9 clicks of +10,000 and 21 clicks of +100

🔹 (c) 1,20,500
🔸 12 × 10,000 = 1,20,000
🔸 5 × 100 = 500
🔸 1,20,000 + 500 = 1,20,500
📌 ✅ Final: 12 clicks of +10,000 and 5 clicks of +100

🔹 (d) 65,30,000
🔸 653 × 10,000 = 65,30,000
📌 ✅ Final: 653 clicks of +10,000 and 0 clicks of +100

🔹 (e) 70,25,700
🔸 702 × 10,000 = 70,20,000
🔸 57 × 100 = 5,700
🔸 70,20,000 + 5,700 = 70,25,700
📌 ✅ Final: 702 clicks of +10,000 and 57 clicks of +100

🔒 ❓ Question 8
How many lakhs make a billion?

📌 ✅ Answer:
🔹 1 lakh = 100,000
🔹 1 billion = 1,000,000,000
🔹 Number of lakhs in a billion = 1,000,000,000 ÷ 100,000 = 10,000

✔️ Final: 10,000 lakhs

🔒 ❓ Question 9
You are given two sets of number cards numbered from 1–9. Place a number card in each box below to get the (a) largest possible sum
(b) smallest possible difference of the two resulting numbers.

📌 ✅ Answer:

🔹 (a) Largest possible sum
🔸 Make both numbers as large as possible by placing the largest digits in the highest places (each set used separately).
✔️ Final: 7-digit number = 9876543, 5-digit number = 98765

🔹 (b) Smallest possible difference
🔸 To minimize the difference, make the 7-digit number as small as possible and the 5-digit number as large as possible (each from its own set).
✔️ Final: 7-digit number = 1234567, 5-digit number = 98765

🔒 ❓ Question 10
You are given some number cards; 4000, 13000, 300, 70000, 150000, 20, 5. Using the cards get as close as you can to the numbers below using any operation you want. Each card can be used only once for making a particular number.
(a) 1,10,000: Closest I could make is 4000 × (20 + 5) + 13000
= 1,13,000
(b) 2,00,000:
(c) 5,80,000:
(d) 12,45,000:
(e) 20,90,800:

📌 ✅ Answer:
🔹 (b) 2,00,000
🔸 150000 + 70000 = 220000
🔸 4000 × 5 = 20000
🔸 220000 − 20000 = 200000
📌 ✅ Final: 150000 + 70000 − (4000 × 5) = 2,00,000

🔹 (c) 5,80,000
🔸 70000 × 5 = 350000
🔸 4000 × 20 = 80000
🔸 150000 + 350000 = 500000
🔸 500000 + 80000 = 580000
📌 ✅ Final: 150000 + (70000 × 5) + (4000 × 20) = 5,80,000

🔹 (d) 12,45,000 (closest)
🔸 70000 + 150000 = 220000
🔸 220000 + 13000 = 233000
🔸 233000 × 5 = 1165000
🔸 4000 × 20 = 80000
🔸 1165000 + 80000 = 1245000
🔸 1245000 + 300 = 1245300
🔸 Difference from 12,45,000 = 1245300 − 1245000 = 300
📌 ✅ Final: 5 × (150000 + 70000 + 13000) + (4000 × 20) + 300 = 12,45,300 (300 more)

🔹 (e) 20,90,800 (closest)
🔸 13000 + 150000 = 163000
🔸 163000 × 5 = 815000
🔸 20 + 4000 = 4020
🔸 4020 × 300 = 1206000
🔸 1206000 + 70000 = 1276000
🔸 815000 + 1276000 = 2091000
🔸 Difference from 20,90,800 = 2091000 − 2090800 = 200
📌 ✅ Final: 5 × (150000 + 13000) + (300 × (4000 + 20)) + 70000 = 20,91,000 (200 more)

🔒 ❓ Question 11
Find out how many coins should be stacked to match the height of the Statue of Unity. Assume each coin is 1 mm thick.

📌 ✅ Answer:
🔹 Height of Statue of Unity = 182 m
🔹 1 mm = 0.001 m
🔸 Number of coins = 182 ÷ 0.001
🔸 Number of coins = 182000
📌 ✅ Final: 1,82,000 coins

🔒 ❓ Question 12
Grey-headed albatrosses have a roughly 7-feet wide wingspan. They are known to migrate across several oceans. Albatrosses can cover about 900–1000 km in a day. One of the longest single trips recorded is about 12,000 km. How many days would such a trip take to cross the Pacific Ocean approximately?

📌 ✅ Answer:
🔹 Fast estimate (1000 km/day):
🔸 Days = 12000 ÷ 1000
🔸 Days = 12

🔹 Slow estimate (900 km/day):
🔸 Days = 12000 ÷ 900
🔸 Days = 13.33 (approx)

📌 ✅ Final: Approximately 12 to 14 days

🔒 ❓ Question 13
A bar-tailed godwit holds the record for the longest recorded non-stop flight. It travelled 13,560 km from Alaska to Australia without stopping. Its journey started on 13 October 2022 and continued for about 11 days. Find out the approximate distance it covered every day. Find out the approximate distance it covered every hour.

📌 ✅ Answer:
🔹 Approximate distance per day
🔸 Total distance = 13560 km
🔸 Total time = 11 days
🔸 Distance per day = 13560/11 km
🔸 Distance per day = 1232.727… km
📌 ✅ Final: Approximately 1233 km per day

🔹 Approximate distance per hour
🔸 Total hours in 11 days = 11 × 24
🔸 Total hours = 264
🔸 Distance per hour = 13560/264 km
🔸 Distance per hour = 51.3636… km
📌 ✅ Final: Approximately 51 km per hour

🔒 ❓ Question 14
Bald eagles are known to fly as high as 4500–6000 m above the ground level. Mount Everest is about 8850 m high. Aeroplanes can fly as high as 10,000–12,800 m. How many times bigger are these heights compared to Somu’s building?

📌 ✅ Answer:

🔹 From the lesson context, Somu’s building height = 10 m.

🔹 Bald eagles
🔸 4500 ÷ 10 = 450
🔸 6000 ÷ 10 = 600
📌 ✅ Final: Bald eagles fly about 450–600 times higher than Somu’s building.

🔹 Mount Everest
🔸 8850 ÷ 10 = 885
📌 ✅ Final: Mount Everest is about 885 times higher than Somu’s building.

🔹 Aeroplanes
🔸 10000 ÷ 10 = 1000
🔸 12800 ÷ 10 = 1280
📌 ✅ Final: Aeroplanes fly about 1000–1280 times higher than Somu’s building.

Class 7 : Maths – Lesson 1. Large Numbers Around Us

EXPLANATION AND ANALYSIS

🔵 Introduction: Large Numbers in Everyday Life

🟢 Place Value: The Basis of Large Numbers

🔵 Indian Place Value System

🟢 International Place Value System

🟡 Reading Large Numbers

🔵 Writing Large Numbers in Numerals

🟢 Comparing Large Numbers

🟡 Ordering Large Numbers

🔵 Estimation and Rounding Off

🟢 Use of Large Numbers in Daily Life

🔴 Common Errors to Avoid

🟢 Importance of Learning Large Numbers

📘 Summary

📝 Quick Recap

TEXTBOOK QUESTIONS

OTHER IMPORTANT QUESTIONS

🔵 Section A – Very Short Answer (1 × 6 = 6 marks)

🟢 Section B – Short Answer I (2 × 6 = 12 marks)

🟡 Section C – Short Answer II (3 × 10 = 30 marks)

🔴 Section D – Long Answer (4 × 8 = 32 marks)

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