Place Value to Millions

Our number system is built on place value: the same digit means different amounts depending on where it stands. Reading from the right, the columns are units, tens, hundreds, then thousands, ten-thousands, hundred-thousands, and then millions.

Each column is worth ten times the column to its right. In the number $4\,372\,015$:

So the digit $3$ is not just "three" — it sits in the hundred-thousands column, so it is worth $300\,000$.

Expanded notation breaks a number into the value of each digit. For example:

(There are no thousands and no hundreds… wait — check carefully: $6$ ten-thousands $= 60\,000$, $0$ thousands, $4$ hundreds $= 400$, $5$ tens $= 50$, $2$ units. Writing every column out like this is a reliable way to avoid place-value slips.)