Question

How do you determine the number of significant figures if a number does not have a decimal place?

Answer 1

It's normally determined by the first and last non-zero digit, but can be otherwise indicated...

Explanation:

By default, the number of significant figures is the number of digits in the run from the first non-zero digit to the last.

For example:

`200340000`

has `5` significant digits, namely "`20034`"

If you are given a number like `80000`, then by default it has just `1` significant digit unless you are told otherwise.

One convention that is sometimes used is to indicate the last significant digit with an overbar or underbar, e.g.

`80bar(0)00`

`80underline(0)00`

These examples have `3` significant figures, namely "`800`"