Writing & Representing Numbers
Using number discs, converting words to numerals, and numerals to words
1. Number Discs
What are Number Discs?
Number discs are circular counters that represent different place values. Each disc shows its value, making it easy to see what a number is made of.
Number Disc Values:
Example: Showing 3,254,132 with Number Discs
Counting: 3 millions + 2 hundred thousands + 5 ten thousands + 4 thousands + 1 hundred + 3 tens + 2 ones = 3,254,132
2. Converting Words to Numerals
Steps to Convert Words to Numbers:
- Look for "million" - the number before it goes in the millions place, with 6 places still to fill after it
- Look for "thousand" - that's the thousands part
- The rest is hundreds, tens, and ones
- Fill in zeros for any missing place values!
⚠️ Watch Out for Zeros!
When a place value isn't mentioned, you need to put a zero there!
Example: "Five million, three hundred" → 5,000,300 (zeros in the hundred thousands, ten thousands, thousands, tens and ones places)
Example: "Five million, one hundred thousand, two hundred and seven"
Step 1: "Five million" → Start with 5,_ _ _, _ _ _
Step 2: "one hundred thousand" → 5,100,_ _ _
No ten thousands and no thousands mentioned, so both are 0
Step 3: "two hundred and seven" → 5,100,207
Two hundred = 2, no tens = 0, seven = 7
Answer: 5,100,207
Example: "Nine million, two hundred and thirty thousand, three hundred and sixty-four"
Step 1: "Nine million" → 9,_ _ _, _ _ _
Step 2: "two hundred and thirty thousand" → 9,230,_ _ _
230 in the thousands section
Step 3: "three hundred and sixty-four" → 9,230,364
Answer: 9,230,364
3. Converting Numerals to Words
Steps to Convert Numbers to Words:
- Split the number into groups of three from the right
- Read the millions group and say "million"
- Read the thousands group and say "thousand"
- Read the last three digits (hundreds, tens, ones)
- Skip zeros - don't say "zero hundred" or "zero thousand"
Example: Write 1,503,080 in words
Step 1: Split: 1 | 503 | 080
millions | thousands | ones
Step 2: Millions: "One million"
Step 3: Thousands: "five hundred and three thousand"
Step 4: Last three (080): "and eighty"
Skip the zero hundreds: say "and eighty"
Answer: One million, five hundred and three thousand and eighty
Quick Reference - Number Words:
1-9:
one, two, three...
10-19:
ten, eleven, twelve...
20, 30, 40...
twenty, thirty, forty...
100s:
one hundred, two hundred, three hundred...
Practice Problems
1. Write these in numerals:
a) Three million, four hundred and fifty thousand, six hundred and twelve
b) Seven million, eight thousand and three
c) Two million, five hundred
ShowHide solutions
a) 3,450,612
b) 7,008,003
c) 2,000,500
2. Write these in words:
a) 4,672,100
b) 8,005,040
c) 3,900,009
ShowHide solutions
a) Four million, six hundred and seventy-two thousand, one hundred
b) Eight million, five thousand and forty
c) Three million, nine hundred thousand and nine
Key Takeaways
- Number discs are visual tools to show place values
- Count discs in each column and add up their values
- When converting words to numerals, don't forget zeros for missing place values
- When converting numerals to words, skip zeros - don't say "zero hundred"
- Split large numbers into groups of three from the right: millions | thousands | ones
- Use "and" before the tens and ones (e.g., "three hundred and forty-five")