# Y9. Number. Multiplying & Dividing by powers of 10

Do we know what number each different power of 10 gives us (e.g 103, 102, 101, 100, 10-1, 10-2, 10-3)?

Our decimal system is set up so that 10 is a very special number (as well as the number of fingers that we have). Because of this multiplying and dividing by powers of 10 is much easier than multiplying and dividing by powers of other numbers. Let’s try a few examples (and not just the ones below):

Examples

Exercise

Let’s complete exercise 4E from pages 65 and 66 of the textbook: