Class 6 full maths Chapters 1 solution

Chapter 1 — Knowing Our Numbers (Full Solutions)

Topics covered: Place value, Indian number system, comparing & arranging numbers, successor & predecessor, forming numbers, rounding, expanded form.

Q1. Write the following in numerals.

• (a) Four lakh seven thousand two hundred nine = 4,07,209
• (b) Eight lakh ninety thousand three = 8,90,003
• (c) Three lakh five thousand five hundred twelve = 3,05,512

Q2. Write the following in words.

• (a) 6,24,385 = Six lakh twenty four thousand three hundred eighty five
• (b) 90,07,001 = Ninety lakh seven thousand one
• (c) 5,05,050 = Five lakh five thousand fifty

Q3. Place value & face value (examples)

Number: 6,24,385, digit underlined: 4 → Face value = 4, Place value = 4 × 1000 = 4000.

Q4. Compare using < , > or =

• 3,00,450 > 3,00,405
• 2,50,001 > 2,05,100
• 45,000 < 4,50,000

Q5. Arrange in ascending order

3,02,105 ; 3,01,512 ; 3,00,999 ; 3,02,100 → Ascending: 3,00,999 , 3,01,512 , 3,02,100 , 3,02,105

Q6. Successor & Predecessor

• 99,999 → Successor = 100,000, Predecessor = 99,998
• 4,37,000 → Successor = 4,37,001, Predecessor = 4,36,999

Q7 & Q8. Form greatest/smallest numbers (examples)

Using digits 0,1,2,3,5,6:

• Smallest 6-digit = 1,02,356
• Greatest 6-digit = 6,53,210

Q9. Rounding off

47,689 → nearest ten: 47,690, nearest hundred: 47,700, nearest thousand: 48,000.

2,49,351 → nearest ten: 2,49,350, nearest hundred: 2,49,400, nearest thousand: 2,49,000.

Q10. Indian system grouping

• 1,234,567 → 12,34,567
• 5,600,450 → 56,00,450

Q11–Q19. Misc. word problems and formations (short answers)

• Sale increase: 3,75,500 − 2,50,000 = 1,25,500
• Population new = 1,25,347 + 3,452 = 1,28,799
• Greatest 7-digit using 0–6 = 65,43,210 → "Sixty five lakh forty three thousand two hundred ten"
• Compare 7,03,000 & 6,95,000 → 7,03,000 > 6,95,000
• Expanded form: 8,23,456 = 800000 + 20000 + 3000 + 400 + 50 + 6
• 4,025 − 175 = 3,850
• Successor examples: 4,99,999 → 5,00,000 ; 9,99,999 → 10,00,000
• Predecessor examples: 1,00,000 → 99,999 ; 2,00,001 → 2,00,000
• Form greatest 5-digit (8,6,4,2,0) = 86,420 ; smallest (no leading zero) = 20,468
• If place value of 7 is 7000 → 7 is in thousands place (since 7×1000 = 7000)

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