Place Value and Rounding | Year 7 Mathematics (Cambridge) PDF Download

Understanding Place Value

Place value is the concept of determining the value of a digit based on its position in a number. It is fundamental for reading, writing, and comparing numbers accurately.

Digits and Positions

• Each digit in a number has a specific place and value.
• Example: In the number 364,
  • Hundreds place: 3 (300)
  • Tens place: 6 (60)
  • Units place: 4 (4)

Reading Large Numbers

• Place value helps in understanding the magnitude of large numbers.
• Example: In the number 5,372,
  • Thousands place: 5 (5000)
  • Hundreds place: 3 (300)
  • Tens place: 7 (70)
  • Units place: 2 (2)

Examples

• Number: 487
  • Hundreds Place: 4 (400)
  • Tens Place: 8 (80)
  • Units Place: 7 (7)
• Number: 1,256
  • Thousands Place: 1 (1000)
  • Hundreds Place: 2 (200)
  • Tens Place: 5 (50)
  • Units Place: 6 (6)

Understanding Rounding Numbers

Rounding numbers involves approximating a number to a specified place value.

Rounding Rules

• Determine the target place value (units, tens, hundreds, etc.).
• Example: Rounding 348 to the nearest tens gives 350.
• Examples:
  • Number: 267
    • Rounded to the Nearest Tens: 270
  • Number: 1,849
    • Rounded to the Nearest Hundreds: 1,800

Key Points

• Place Value: Essential for understanding the hierarchical structure of numbers.
• Rounding: Useful for estimating and simplifying numerical values while maintaining relative accuracy.