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Numbers & Operations

5- and 6-digit Numbers & Place Value

In the Indian system, after the Hundreds, Tens and Ones come Thousands, Ten Thousands and Lakhs. A 6-digit number such as 4,52,310 has 4 Lakhs, 5 Ten Thousands, 2 Thousands, 3 Hundreds, 1 Ten and 0 Ones.

The smallest 6-digit number is 1,00,000 (one lakh) and the largest is 9,99,999. The place of a digit gives its value, so the 5 in 4,52,310 stands for 50,000.

Example 1: What is the place value of 5 in 4,52,310?
5 is in the Ten Thousands place, so its value is 50,000.
Example 2: Write the smallest and largest 6-digit numbers.
Smallest = 1,00,000 and largest = 9,99,999.
Quick recap
  • Indian places: Ones, Tens, Hundreds, Thousands, Ten Thousands, Lakhs.
  • Smallest 6-digit number = 1,00,000; largest = 9,99,999.
✓ Quick check
What is the place value of 7 in 7,30,425?
7 is in the Lakhs place, so its value is 7,00,000.
What is the smallest 5-digit number?
The smallest 5-digit number is 10,000.

Rounding & Adding/Subtracting Large Numbers

To round a number, look at the digit just after the place you are rounding to. If it is 5 or more, round up; otherwise round down. So 4,567 rounded to the nearest 1000 is 5,000.

Large numbers are added and subtracted column by column, carrying or borrowing exactly as with smaller numbers.

Example 1: Round 4,567 to the nearest thousand.
The hundreds digit 5 is 5 or more, so it rounds up to 5,000.
Example 2: Subtract 80,000 − 35,600.
80,000 − 35,600 = 44,400.
Quick recap
  • Round up if the next digit is 5 or more, else round down.
  • Add and subtract large numbers column by column.
✓ Quick check
Round 3,482 to the nearest hundred.
The tens digit 8 is 5 or more, so it rounds up to 3,500.
Add: 25,340 + 14,260 = ?
25,340 + 14,260 = 39,600.

Multiplication & Division of Large Numbers

To multiply a 3-digit number by a 2-digit number, multiply by the ones and the tens separately, then add. For 234 × 12: 234 × 2 = 468 and 234 × 10 = 2,340, so 468 + 2,340 = 2,808.

To divide, share place by place from the left. For 4,824 ÷ 6 = 804, and we can check with 804 × 6 = 4,824.

Example 1: Multiply 234 × 12.
234 × 2 = 468, 234 × 10 = 2,340, total 2,808.
Example 2: Divide 4,824 ÷ 6.
4,824 ÷ 6 = 804. Check: 804 × 6 = 4,824.
Quick recap
  • Multiply by ones and tens separately, then add.
  • Check division using multiplication.
✓ Quick check
Multiply: 312 × 3 = ?
3 × 312 = 936.
Divide: 4,000 ÷ 8 = ?
8 × 500 = 4,000, so 4,000 ÷ 8 = 500.
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