Explanation of Rounding Off Numbers
Rounding off numbers means adjusting a number to its nearest place value (nearest tens, hundreds, thousands, etc.). We follow these general rules:
- Rule 1: If the digit to be dropped is less than 5, keep the preceding digit the same.
- Rule 2: If the digit to be dropped is 5 or more, increase the preceding digit by 1.
Types of Rounding Off:
- Rounding to the Nearest Ten
- Rounding to the Nearest Hundred
- Rounding to the Nearest Thousand
- Rounding to the Nearest Ten Thousand
- Rounding to the Nearest Lakh
Solved Examples
1. Rounding to the Nearest Ten
- 47 → 50 (7 is greater than 5, so round up)
- 63 → 60 (3 is less than 5, so round down)
- 78 → 80
- 124 → 120
- 139 → 140
- 305 → 310
- 492 → 490
- 817 → 820
- 954 → 950
- 999 → 1,000
2. Rounding to the Nearest Hundred
- 163 → 200 (63 is greater than 50, so round up)
- 247 → 200 (47 is less than 50, so round down)
- 382 → 400
- 515 → 500
- 649 → 600
- 782 → 800
- 899 → 900
- 950 → 1,000
- 1,174 → 1,200
- 1,489 → 1,500
3. Rounding to the Nearest Thousand
- 1,438 → 1,000 (438 is less than 500, so round down)
- 2,789 → 3,000 (789 is greater than 500, so round up)
- 5,612 → 6,000
- 9,875 → 10,000
- 14,234 → 14,000
- 23,567 → 24,000
- 35,499 → 35,000
- 47,805 → 48,000
- 58,999 → 59,000
- 69,501 → 70,000
4. Rounding to the Nearest Ten Thousand
- 23,567 → 20,000 (3,567 is less than 5,000, so round down)
- 35,499 → 30,000
- 47,805 → 50,000
- 58,999 → 60,000
- 69,501 → 70,000
- 84,456 → 80,000
- 91,632 → 90,000
- 105,123 → 110,000
- 214,678 → 210,000
- 398,999 → 400,000
5. Rounding to the Nearest Lakh
- 2,78,456 → 3,00,000
- 1,32,876 → 1,00,000
- 4,92,345 → 5,00,000
- 5,16,982 → 5,00,000
- 6,89,123 → 7,00,000
- 7,45,678 → 7,00,000
- 8,99,999 → 9,00,000
- 9,11,654 → 9,00,000
- 10,34,789 → 10,00,000
- 12,99,999 → 13,00,000
Home Work Worksheet
Section 1: Rounding to the Nearest Ten
- 56 → ?
- 89 → ?
- 124 → ?
- 298 → ?
- 503 → ?
Section 2: Rounding to the Nearest Hundred
- 645 → ?
- 1,234 → ?
- 3,567 → ?
- 7,892 → ?
- 9,999 → ?
Section 3: Rounding to the Nearest Thousand
- 1,678 → ?
- 4,899 → ?
- 7,123 → ?
- 10,345 → ?
- 24,678 → ?
Section 4: Rounding to the Nearest Ten Thousand
- 23,890 → ?
- 36,789 → ?
- 45,432 → ?
- 58,899 → ?
- 69,567 → ?
Section 5: Rounding to the Nearest Lakh
- 1,23,678 → ?
- 2,56,987 → ?
- 4,78,543 → ?
- 5,99,999 → ?
- 8,34,123 → ?