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Large Numbers Around Us – Class 7 Mathematics notes, important questions and MCQs

NCERT Class 7 Mathematics, chapter 1. Notes, key terms, important questions with answers and MCQs.

Chapter overview

Large numbers are read using place value. India uses lakhs and crores; the international system uses millions and billions.

Place value systems

Indian: ones, tens, hundreds, thousands, ten thousands, lakhs, ten lakhs, crores (commas 3, then 2, 2: 1,23,45,678).
International: thousands, millions, billions (commas every 3 digits: 12,345,678).
1 lakh = 100 thousand; 1 million = 10 lakh; 1 crore = 10 million.

Working with large numbers

Compare by counting digits, then compare from the left.
Estimate by rounding to the nearest ten, hundred or thousand.

Key terms

Lakh: 1,00,000 (one hundred thousand)
Crore: 1,00,00,000 (ten million)
Estimation: finding a rough value by rounding

Formulas

1 million = 10,00,000; 1 billion = 100 crore

Important questions with answers

Write 7,05,08,030 in words (Indian system).2 marks

Seven crore five lakh eight thousand thirty.

Write 52,407,300 in the Indian system with commas and in words.3 marks

5,24,07,300: five crore twenty-four lakh seven thousand three hundred.

A city has a population of 1,25,48,762. Round it to the nearest lakh and nearest crore. If the population grows by about 2,50,000 each year, estimate it after 4 years.5 marks

Nearest lakh: 1,25,00,000 (48,762 < 50,000). Nearest crore: 1,00,00,000 (25,48,762 < 50,00,000). Growth in 4 years ≈ 4 × 2,50,000 = 10,00,000. Estimated population ≈ 1,25,48,762 + 10,00,000 = 1,35,48,762, about 1.35 crore.

Quick revision

10 lakh = 1 million.
More digits = larger whole number.
1 crore = 100 lakh.

Exam tips

In Indian commas, after the first three digits from the right, put commas every two digits.
Round only at the end of a calculation unless asked to estimate.

Practice MCQs

One lakh has how many zeros?
1. 4
2. 5
3. 6
4. 7
Show answer
Answer: (b) 5. 1,00,000.
10 lakh equals
1. 1 crore
2. 1 million
3. 1 billion
4. 100 thousand
Show answer
Answer: (b) 1 million. 1,000,000.
7,05,32,014 in words is
1. seven crore five lakh thirty-two thousand fourteen
2. seventy lakh five hundred thirty-two
3. seven crore fifty lakh
4. seven million five lakh
Show answer
Answer: (a) seven crore five lakh thirty-two thousand fourteen. Indian system.
4,876 rounded to the nearest hundred is
1. 4,800
2. 4,900
3. 5,000
4. 4,870
Show answer
Answer: (b) 4,900. 76 ≥ 50 rounds up.
1 crore equals
1. 10 lakh
2. 100 lakh
3. 1000 lakh
4. 1 million
Show answer
Answer: (b) 100 lakh. 1,00,00,000.
How many lakhs make 3 crore?
1. 30
2. 3
3. 3000
4. 300
Show answer
Answer: (d) 300. 1 crore = 100 lakh.
25 million in the Indian system is
1. 25 lakh
2. 250 crore
3. 25 crore
4. 2.5 crore
Show answer
Answer: (d) 2.5 crore. 25 × 10 lakh = 250 lakh = 2.5 crore.
4,56,78,912 rounded to the nearest lakh is
1. 4,56,00,000
2. 4,57,00,000
3. 4,60,00,000
4. 4,56,80,000
Show answer
Answer: (b) 4,57,00,000. 78,912 ≥ 50,000, so round up.

All chapters of Class 7 Mathematics

Written by Kundali IQ from standard, well-established facts to help with revision. This is not an official NCERT publication; always read your textbook too.