Addition and subtraction up to 10,000 — Year 5 introduction

Addition and subtraction up to 10,000 — Year 5 introduction

Addition and subtraction up to 10,000

In Year 4 you worked with numbers up to one thousand. This year we go one step further — all the way up to ten thousand. The good news is that every trick you already know still works. There's just one new place: the thousands.

How big is a four-digit number?

A four-digit number has four digits. The smallest is 1,000 and the largest is 9,999. Right after it comes 10,000 — ten thousand, the first five-digit number.

7
thousands
3
hundreds
5
tens
8
ones

The number 7,358 reads as seven thousand three hundred fifty-eight. We put a comma (or a small space) between the thousands and the hundreds so the number is easier to read.

Two ways to compute

When adding or subtracting up to 10,000, two methods are useful:

  1. Mentally — when the numbers are round or simple.
3,000 + 4,000 is just like 3 + 4, but in thousands: 7,000.
  1. Written, column by column — when the numbers are messy and you have to carry across several places.
This is the safe method when mental tricks aren't enough.

What's in this chapter

In this chapter you'll learn step by step:

  1. Column addition and subtraction — step by step, with carrying and borrowing.
  2. Mental strategies and patterns — how to compute quickly without paper.
  3. Word problems up to 10,000 — money, distance, populations.

And when you're ready:

Try it now

We've prepared exercises you can run right away. Each one has its own problem generator and gives you different numbers every time:

Click, solve a few problems, and come back if you forget a rule.