Four hundred twenty-three
Standard form: Writing numbers using digits (e.g., 423) instead of words
- Identify the place values in the word form
- Write the corresponding digits in the correct positions
- Fill any missing place values with zeros
- Verify the result matches the original meaning
Four hundred = 400
Twenty = 20
Three = 3
Hundreds place: 4
Tens place: 2
Ones place: 3
4 in hundreds place, 2 in tens place, 3 in ones place
Standard form: 423
423 = 400 + 20 + 3 = four hundred twenty-three ✓
Four hundred twenty-three in standard form is 423
• Place value system: Each position represents a power of 10
• Word to digit conversion: Translate each component to its numeric value
• Positioning: Place digits in correct place value positions
Express as sum of place values
Expanded form: Writing a number as the sum of the value of each digit
5 is in the hundreds place: 5 × 100 = 500
6 is in the tens place: 6 × 10 = 60
7 is in the ones place: 7 × 1 = 7
567 = 500 + 60 + 7
500 + 60 + 7 = 567 ✓
567 = (5 × 100) + (6 × 10) + (7 × 1)
567 in expanded form is 500 + 60 + 7
• Place value multiplication: Each digit multiplied by its place value
• Summation: All place values are added together
• Verification: The sum should equal the original number
Which is greater and why?
Number comparison: Determining which number is larger using place value
Hundreds: 3 vs 3 (equal)
Tens: 4 vs 5 (4 < 5)
Since 4 < 5 in the tens place, 345 < 354
345 = 300 + 40 + 5
354 = 300 + 50 + 4
354 - 345 = 9, confirming 354 is greater
354 is greater than 345 because the tens digit in 354 (5) is greater than in 345 (4)
• Left-to-right comparison: Start with highest place value
• Place value significance: Higher place values have greater impact
• Digit comparison: Compare corresponding digits in each place value
Standard form: Writing numbers using digits (e.g., 423)
Word form: Writing numbers using words (e.g., four hundred twenty-three)
Expanded form: Writing numbers as the sum of place values (e.g., 400 + 20 + 3)
Place value: Value of a digit based on its position in a number
Base ten system: Number system where each place value is 10 times the previous
- Identify the form: Determine if given in standard, word, or expanded form
- Extract place values: Find the value of each digit position
- Convert as needed: Change between different number forms
- Verify results: Check that conversions are accurate
• Place value: Digit × (10^n) where n is position from right (starting at 0)
• Expanded form: Number = Σ(digit × place value)
• Comparison: Compare digits from left to right until difference found
• Standard form: Write digits in correct place value positions
a) 600 + 40 + 8 to standard form
b) 275 to word form
Form conversion: Changing between standard, word, and expanded forms
600 + 40 + 8 = 648
6 in hundreds place, 4 in tens place, 8 in ones place
275: 2 in hundreds place → "two hundred"
75: read as "seventy-five"
Combined: "two hundred seventy-five"
Part a: 648 = 600 + 40 + 8 ✓
Part b: 275 = two hundred seventy-five ✓
a) 600 + 40 + 8 = 648 in standard form
b) 275 = two hundred seventy-five in word form
• Expanded to standard: Sum all place values
• Standard to word: Read each place value component
• Verification: Check that conversions are accurate
Write it in all three forms.
Problem solving: Using place value information to write number in different forms
Hundreds place: 3
Tens place: 6
Ones place: 2
Standard form: 362
362 = three hundred sixty-two
362 = 300 + 60 + 2
300 + 60 + 2 = 362 ✓
Three hundred sixty-two = 362 ✓
Standard form: 362, Word form: three hundred sixty-two, Expanded form: 300 + 60 + 2
• Place value identification: Use given place values to construct number
• Form conversion: Convert between all three standard forms
• Verification: Ensure all forms represent the same number
Standard form: Writing numbers using digits (numerals) in their correct place value positions
Word form: Writing numbers using words to describe the value of each digit
Expanded form: Writing numbers as the sum of each digit multiplied by its place value
Place value: The value of a digit determined by its position in the number
Base ten system: Decimal system where each place value is 10 times the previous
- Number identification: Recognize place values in given numbers
- Form recognition: Identify which form the number is currently in
- Conversion planning: Determine which form to convert to
- Conversion execution: Apply appropriate conversion method
- Verification: Check that all forms represent the same value
• Place value formula: Position n from right has value digit × 10^(n-1)
• Expanded form: N = d₁×10^(k-1) + d₂×10^(k-2) + ... + dₖ×10⁰
• Standard to word: Read each place value component
• Word to standard: Identify place values and write digits
\(N_1: 123\) (standard form)
\(N_2: \text{one hundred twenty-three}\) (word form)
\(N_3: 100+20+3\) (expanded form)
Analysis: The visualization shows how all three forms represent the same value.
- \(N_1\): Standard form shows digits in place value positions
- \(N_2\): Word form describes the number using language
- \(N_3\): Expanded form breaks down the number by place values