To convert concentrations in the parts per notation, follow the next few steps:
From your number...
Multiply by 100 to find the percentage (part per 100);
Multiply by 1,000 to find the permille (or multiply the percentage by 10);
Multiply by 1,000,000 to find the parts per million (PPM), or multiply the permille by 1000, or the percentage by 10,000;
Multiply by 1,000,000,000 to find the parts per billion (PPB);
Multiply by 1,000,000,000,000 to find the parts per trillion (PPT).
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