Numbers Up to 10,000
1. Place Value (Thousands, Hundreds, Tens, Ones)
Every number is made of DIGITS. Each digit has a PLACE and a VALUE.
'In the number 3,456 — the digit 3 is in the THOUSANDS place and means 3,000. The digit 4 is in the HUNDREDS place and means 400.'
Place Value Chart:
| Thousands (Th) | Hundreds (H) | Tens (T) | Ones (O) |
|---|---|---|---|
| 1,000 | 100 | 10 | 1 |
Example: The number 3,456
- 3 in Thousands place → 3,000
- 4 in Hundreds place → 400
- 5 in Tens place → 50
- 6 in Ones place → 6
Reading Numbers:
3,456 = Three thousand four hundred fifty-six
| Number | In Words |
|---|---|
| 1,000 | One thousand |
| 2,345 | Two thousand three hundred forty-five |
| 5,678 | Five thousand six hundred seventy-eight |
| 9,999 | Nine thousand nine hundred ninety-nine |
| 10,000 | Ten thousand |
'Read the THOUSANDS group first, then the remaining three digits. 4,567 = Four thousand five hundred sixty-seven.'
2. Expanded Form
Write the number as the SUM of its place values.
Examples:
- 3,456 = 3,000 + 400 + 50 + 6
- 5,820 = 5,000 + 800 + 20 + 0 (or 5,000 + 800 + 20)
- 7,009 = 7,000 + 0 + 0 + 9 = 7,000 + 9
Practice:
Write 6,789 in expanded form.
Answer: 6,000 + 700 + 80 + 9
'If a place has ZERO, you can skip it in expanded form. But in the NUMBER, the zero is important because it HOLDS the place!'
| Number | Expanded Form |
|---|---|
| 2,305 | 2,000 + 300 + 0 + 5 |
| 4,080 | 4,000 + 0 + 80 + 0 |
| 9,999 | 9,000 + 900 + 90 + 9 |
| 1,001 | 1,000 + 0 + 0 + 1 |
3. Comparing Numbers
Rules:
- A number with MORE digits is ALWAYS larger.
- If both have the SAME number of digits, start comparing from the LEFT.
Examples:
- 5,678 > 999 (4 digits > 3 digits)
- 6,789 > 5,789 (same 4 digits — 6 > 5 in thousands)
- 7,890 < 8,901 (same 4 digits — 7 < 8 in thousands)
- 4,567 > 4,566 (same up to tens — 7 > 6 in ones)
| First Number | Second Number | Which Is Larger? |
|---|---|---|
| 4,567 | 4,657 | 4,657 (4,6 > 4,5) |
| 8,901 | 8,910 | 8,910 (8,91 > 8,90) |
| 3,333 | 3,330 | 3,333 (3 > 0 in ones) |
| 1,000 | 10,000 | 10,000 (5 digits > 4) |
4. Ordering Numbers
Ascending Order (Smallest to Largest):
Arrange: 3,456, 2,789, 4,567, 1,234 Answer: 1,234 < 2,789 < 3,456 < 4,567
Descending Order (Largest to Smallest):
Arrange: 3,456, 2,789, 4,567, 1,234 Answer: 4,567 > 3,456 > 2,789 > 1,234
5. Skip Counting
Counting by 2s (Even Numbers):
2, 4, 6, 8, 10, 12, 14, 16, 18, 20...
Counting by 5s:
5, 10, 15, 20, 25, 30, 35, 40, 45, 50...
Counting by 10s:
10, 20, 30, 40, 50, 60, 70, 80, 90, 100...
Counting by 100s:
100, 200, 300, 400, 500, 600, 700, 800, 900, 1000...
| Skip by | Start | Next 5 Numbers |
|---|---|---|
| 2 | 4 | 6, 8, 10, 12, 14 |
| 5 | 10 | 15, 20, 25, 30, 35 |
| 10 | 30 | 40, 50, 60, 70, 80 |
| 100 | 300 | 400, 500, 600, 700, 800 |
6. Roman Numerals (I to C)
Roman numerals use LETTERS for numbers.
| Roman | I | V | X | L | C |
|---|---|---|---|---|---|
| Value | 1 | 5 | 10 | 50 | 100 |
Rules:
- Add when smaller comes after: VI = 5 + 1 = 6
- Subtract when smaller comes before: IV = 5 - 1 = 4
Numbers 1 to 20:
I=1, II=2, III=3, IV=4, V=5, VI=6, VII=7, VIII=8, IX=9, X=10, XI=11, XII=12, XIII=13, XIV=14, XV=15, XVI=16, XVII=17, XVIII=18, XIX=19, XX=20
Tens:
XX=20, XXX=30, XL=40, L=50, LX=60, LXX=70, LXXX=80, XC=90, C=100
7. Common Mistakes
- Reading numbers wrong: '4,567 is "four thousand five hundred sixty-seven." NOT "four thousand five hundred and sixty-seven." Avoid using "and" between hundreds and tens.'
- Place value confusion: 'In 3,045, the 0 in hundreds means there are NO hundreds. The number is three thousand forty-five.'
- Comparing digits incorrectly: '4,567 vs 4,657 — compare the hundreds first. 5 vs 6. 6 is bigger, so 4,657 is larger.'
- Roman numeral order: 'IV is 4 (1 before 5). VI is 6 (5 before 1). The order matters!'
8. Key Facts to Remember
- 'The largest 4-digit number is 9,999. The smallest 4-digit number is 1,000.'
- '10 thousands = 10,000 = Ten thousand.'
- 'Skip counting helps you learn multiplication tables.'
- 'Roman numerals I, V, X, L, C represent 1, 5, 10, 50, 100.'
- 'V, L are never repeated. Only I, X, C can be repeated.'
9. Self-Test
Q1: Write 5,678 in words.
Q2: Write in expanded form: 7,305
Q3: Which is larger — 4,567 or 4,657? Why?
Q4: Arrange in ascending order: 3,210, 2,301, 1,230, 3,021
Q5: Write the Roman numerals for: (a) 8 (b) 14 (c) 20 (d) 40
Q6: Convert to Hindu-Arabic: (a) XII (b) XXV (c) XL (d) LXX
Q7: Count by 5s from 15 to 40.
Q8: What is the place value of 7 in 7,845?
Answers:
A1: Five thousand six hundred seventy-eight. A2: 7,000 + 300 + 0 + 5 = 7,000 + 300 + 5 A3: 4,657 — because 6 > 5 in the hundreds place. A4: 1,230 < 2,301 < 3,021 < 3,210 A5: (a) VIII (b) XIV (c) XX (d) XL A6: (a) 12 (b) 25 (c) 40 (d) 70 A7: 15, 20, 25, 30, 35, 40 A8: 7 is in the THOUSANDS place — value = 7,000.
