First of all, we will use the first two panels on the cloth to lay out the two numbers we are adding together. I am going to do the sum 23 + 11.
Adding is the action of shoving them together:
And Bob's your uncle.
Let's try 23 + 44.
Lay them out:
Argh, we have lots of counters! We need to tidy up!
What can we reduce? Start at the bottom... There are more than five counters in the 1s row, so remove them and replace with one counter in the 5s row. There are also more than five counters in the 10s row, so remove them and replace with one counter in the 50s row.
That's better
Try various additions for yourself before going on to subtraction.
Start simply: 10+21, 34+11, 24+41
A little harder: 383+201, 319+74
For a worked example of 201+319, which has a lot of tidying up to do, look at 201+319 worked answer.
For a bit of a challenge, try 383+201, 1584+384, 1968+47, 1210+789.
Go to:
Subtraction
Multiplication
Division
Introduction
