Everyone, not only when in school, needs—from time to time—to convert between fractions, decimals, and percentages, in any direction.
To make it quick and easy, let's first check how it works when we compare the basics:
1/2 = 0.5 = 50%
Always think about some simple example – it really helps!
- Fractions to Decimals: Just divide it (because a fraction line means dividing, good to know, right?). If you don't simply remember it already (like me, for example – because I know how to convert many fractions without thinking, simply by using the conversion so often that I remember many fractions and their decimal notation), divide it either on paper (more effort, but always possible) or with a calculator (when you have one).
- Decimals to Percentages: Multiply by 100, because "percentage" literally means "value per one hundred." And multiplying by one hundred is very easy: just "move" the decimal point two positions to the right (to make a bigger number, not smaller).
- Percentages to Fractions: The best way is to go to decimals first, as written below:
- Percentages to Decimals: This means the reverse operation of multiplying before: divide by 100 ("move" the decimal point two positions to the left, to make a smaller number).
- Decimals to Fractions: If you don't simply remember the fractional notation of the decimal (the more you work with them, the more you remember without working it out), write it first as a fraction of an appropriate power of ten (tenths would be over 10, hundredths over 100, etc.) and simplify it, if possible, afterwards.
- Fractions to Percentages: To close the circle, again, it's better to go through one additional step—using decimals first, as described above already.
One important note at the end, which I believe is worth mentioning: the example above expresses the same number, just in different notations. That's why it's all equal; that's why I used equal signs between all three (notations of the) numbers.
Need more help with decimals, fractions and percentages? Well, then, you're lucky! I have a free minicourse on fractions, decimals, and percentages.
