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Place Value & Number Line Questions

Maths · Year 3 NAPLAN
Year 3
Lesson Guide
Explanation
Every digit has a place, and the place tells you what the digit is worth. In five hundred and sixty-four, the five sits in the hundreds place, so it is worth five hundred — not five. The whole number is five hundred plus sixty plus four. Watch out for a zero: five hundred and four is five hundred plus four, with no tens at all. The test likes to offer five plus six plus four as a wrong answer, so check the places and not just the digits.
Your Turn
Write 307 as hundreds, tens and ones added up. Check: 300 + 7, with no tens.
Watch Out
564 is not 5 + 6 + 4. Each digit is worth what its place says.
Explanation
A four-digit number has one more place on the left, the thousands. Four thousand eight hundred and seven is four thousands, eight hundreds, no tens and seven ones. To compare two numbers, start from the left: four thousand eight hundred and seven beats four thousand seven hundred and eighty because eight hundreds beats seven hundreds. If the first digits match, look at the next one along and keep going until they are different. And a number with more digits is always bigger — a thousand beats nine hundred and ninety-nine.
Your Turn
Which is bigger, 4807 or 4780? Check: 4807, because 8 hundreds beats 7 hundreds.
Watch Out
Compare from the LEFT, not the right. The first place where they differ decides it.
Explanation
A number line does not always go up in ones. Before you read anything, work out what one step is worth: take two labels, subtract, and count the steps between them — and count the steps, not the ticks, because six ticks make only five steps. From nought to fifty with five steps, each step is ten. Then count the steps to the arrow. Never guess a number from how far along the line it looks.
Your Turn
Labels at 0 and 50 with 5 steps between. What is one step worth? Check: 10.
Watch Out
Count the gaps between the ticks, not the ticks themselves.
Explanation
To find the number halfway between two others, add them together and halve. Two hundred and eighty-five plus three hundred and twenty-five is six hundred and ten, and half of that is three hundred and five. You can also count in from both ends until you meet in the middle. Then check it: three hundred and five take two hundred and eighty-five is twenty, and three hundred and twenty-five take three hundred and five is also twenty. The same gap on both sides, so it really is the middle.
Your Turn
What is halfway between 40 and 60? Check: 50 — and 50 − 40 = 10 = 60 − 50.
Watch Out
Check both gaps are the same. If they are not, your answer is not halfway.
Explanation
Four things cover this strand. Check what each digit is worth by its place. Compare numbers from the left. On a number line, find what one step is worth before reading anything. And for halfway, add the two numbers and halve, then check the gaps match. The number line questions are the ones worth practising most, because they are where the marks go. Quiz and exercises now.
Your Turn
What is the 4 in 4807 worth? Check: 4000.
Watch Out
Read whether the question wants the digit or what it is WORTH. Those are different answers.
📌 Key Points — this lesson in a nutshell
  • Each digit has a place, and the place tells you what the digit is worth.
  • 564 = 500 + 60 + 4. Watch for a zero: 504 is 500 + 4, with no tens at all.
  • On a number line, work out what one step is worth before you read anything.
  • Halfway between two numbers: add them and halve, or count in from both ends.
Step 1: Introduction
Step 1 of 5
564 in a place value chart millionshundredthousandstenthousandsthousandshundreds5tens6ones4 500+ 60560+ 4564 564 is 5 hundreds, 6 tens and 4 ones — so 500 + 60 + 4. The 5 is not worth 5. It sits in the hundreds place, so it is worth 500. Careful with a zero: 504 is 500 + 4. There are no tens, so nothing goes in the middle. The test often offers 5 + 6 + 4 as a wrong answer. Check the places, not the digits.
Numbers beyond three digits millionshundredthousandstenthousandsthousands4hundreds8tens0ones7 4807 is 4 thousands, 8 hundreds, no tens and 7 ones: 4000 + 800 + 7. A four-digit number has one more place on the left: thousands. To compare two numbers, start from the LEFT. 4807 beats 4780 because 8 hundreds beats 7 hundreds. If the first digits match, look at the next one along, and keep going until they differ. A number with more digits is always bigger: 1000 beats 999.
The steps are not always 1 050100 labels every 50, a tick every 10 0 to 505 ticks50 ÷ 5one step10 Count the STEPS between two labels, not the ticks. 6 ticks make 5 steps. From 0 to 50 there are 5 steps, so each step is 10. Then count the steps to the arrow. Never guess a number from how far along it looks.
Halfway between 285 and 325 285325? 285 + 325= 610610 ÷ 2halfway305 Add the two numbers and halve. 285 + 325 = 610, and half of 610 is 305. Or count in from both ends at the same time until you meet in the middle. Check it: 305 − 285 = 20, and 325 − 305 = 20. The same both sides, so it really is the middle. That check is the important bit. If the two gaps are different, it is not halfway.
What the test asks Which one equals 564?500 + 60 + 4 What is the 8 in 4807 worth?800 Labels every 50, ticks every 10. One step?10 Halfway between 285 and 325?305 Check the place · compare from the left · find one step · add and halve. Four things, and the number line ones are worth practising most. Quiz and exercises now.
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