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Composing and Decomposing Numbers


Composing and Decomposing Numbers

Composing

So 349 is composed of 3 hundreds, 4 tens and 9 ones, in other words:


300 + 40 + 9  ⇒  349
"Composing"


Example: Compose 2 hundreds, 7 tens and 9 ones.

200 + 70 + 9 = 279



Decomposing

Decomposing is when we break the number apart:

349  ⇒  300 + 40 + 9
"Decomposing"

Example: Decompose 3,456

3,456 = 3,000 + 400 + 50 + 6



Standard and Expanded Form

Some people call the two different forms "Standard" and "Expanded":

Standard and Expanded Form picture

 

Example: Put 925 into Expanded Form

925 = 900 + 20 + 5



Decimal Numbers

We can also compose and decompose decimal numbers

37.2  ⇒  30 + 7 + 0.2
"Decomposing"

 

4 + 0.7 + 0.08  ⇒  4.78
"Composing"

 

Example: Decompose 1.35

1.35 = 1 + 0.3 + 0.05


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