How to convert parts per million to percent?

Answer:
Parts per million is a fraction with denominator 1,000,000.

For example 5 parts per million means 5/1,000,000.


Percent is a fraction with denominator 100.
For example, 5 percent is 5/100.

So your goal is to convert a fraction with denominator 1,000,000 into a fraction with denominator 100.

Let's work an example:
5 parts per million means 5/1,000,000.
The rules of fractions allow us to multiply the numerator and denominator by the same number (except 0).
So multiply numerator and denominator by .0001 and we get
.0005/100.
Another word for .0005/100 is .0005 percent.

So the general rule is multiply the parts per million by .0001 or divide by 10,000 (same thing).

First answer by ID2101145904. Last edit by Dracular. Contributor trust: 115 [recommend contributor recommended]. Question popularity: 1 [recommend question].