Decimals: Multiplying by 100

When we multiply numbers by 100, we do not simply add 00 to the end.

When the numbers are decimals, this rule does not work.

54.6 × 100 does not equal 54.600

When we multiply numbers by 100, each digit must move two places to the left.  

When we look at the columns in a Th, H, T, U grid we notice that Thousands are 100 times bigger than Tens, Hundreds are 100 times bigger than units, Tens are 100 times bigger than tenths etc...

*Note that the U for Units is another term for Ones.

e.g. Work out:

54.6 × 10 = 5460 

Here is 54.6 in a Th, H, T, U grid.

Answer:

Each digit moves two places to the left.

Remember to fill in that 0 in the units column.

So  54.6 × 100 = 5460