Study Guide 1/2 G05 ~ Mathematics
Unit
1
The 8 in the Units box means there are 8 Units. We can also write it as 8 × 1. Can you see there are no numbers in the Tens and Hundreds boxes? This means there are 0 × Tens and 0 × Hundreds in this number. Let’s see what happens with a number greater than 9.
Hundreds
Tens
Units
18
There may only be one number in each box, but now there is a 1 and an 8 in the Units box. What does the 18 mean? It consists of 10 + 8.
The 8 is in the Units box and it means 8 × 1, which is shown as 8. The 10 jumps over the wall into the Tens box.
You CANNOT carry the full 10 across, because it then indicates 10 × Tens, which means 10 × 10 which equals 100. Therefore, only the 1 jumps across.
Hundreds
Tens
10
Units
8
1 × Ten means 1 × 10 = 10 If you want to indicate the place value of 18, it will look like this::
Hundreds
Tens
1
The same happens when there is a number greater than 9 in the Tens box.
Hundreds
Tens
86 27
Units
8
Units
8
© Optimi