The idea in brief. Each place adds quantities of the same size; ten in one place become one in the next place. Line up the places and include each carried value. In the lesson. In Primary 2, you added in columns and renamed ten ones as one ten. Ten hundreds make one thousand. Today, we add numbers up to ten thousand in columns, from the ones to the thousands. Line up the places, start with the ones, and rename ten of a place as one of the next place.
Lesson video, with the working
Adding up to four digits
5 min 31 s
The film teaches 3 questions in turn. Each question shows first; its working is written as the film explains it.
How do P3 children solve adding 4-digit numbers questions with renaming?
This page teaches the column method for adding numbers up to 4 digits, the MOE Primary 3 outcome on addition algorithms.
What your child learns here
This page teaches the column method for adding numbers up to 4 digits, the MOE Primary 3 outcome on addition algorithms. It extends the renaming children met with tens and ones to hundreds and thousands, and applies it to total word problems.
Set out an addition in columns, with ones under ones, tens under tens, hundreds under hundreds and thousands under thousands.
Add from the ones to the thousands, renaming 10 ones as 1 ten, 10 tens as 1 hundred and 10 hundreds as 1 thousand.
Add a 3-digit number to a 4-digit number without shifting the shorter number to the left.
Use addition in word problems that ask for a total, and notice when a problem gives the total and asks for a part instead.
Does the answer make sense?
When the question asks for a sum, your child can check that it is bigger than each number being added, and that its thousands digit is at least the thousands digits added together. When a whole number is missing from an addition instead, it must be smaller than the total it helps to make.
How to practise these questions
The Basic questions practise lining up the places and adding column by column. The Intermediate questions add regrouping, where a column makes 10 or more and carries into the next place. In the Challenge questions, your child finds a missing number from the total of three numbers, or from two sums that have the same value. When an addition stalls, play the solution film for that question and try it again later from Revision.
Questions parents ask
Is 4-digit addition in the Primary 3 syllabus? Yes. The MOE Primary 3 syllabus lists addition and subtraction algorithms with numbers up to 4 digits, under Addition and Subtraction. This page covers the addition half.
Is renaming the same as carrying or regrouping? Yes, they all describe the same step: 10 of one place become 1 of the next place. The MOE syllabus and this page say renaming, but you may hear carrying or regrouping elsewhere.
Should my child add from the left or the right? In column addition, start from the ones on the right and move left, so any renaming passes on to the next place. Adding from the left is handy for a rough estimate, but the written method on this page starts with the ones.
