Fractions and Percentages
The term percent means "per hundred" or "for every hundred". It refers to the specific number for every one hundred of something. The symbol for percent is %.
Here are examples of common fractions and their equivalents in percent:
1/2 = 50%
1/3 = 33.33%
1/4 = 25%
1/5 = 20%
1/8 = 12.5%
1/10 = 10%
1/100 = 1%
Let's take an example:
"In this school, 10% of the students are Asians."
The statement above means for every 100 students in the school, 10 of them are Asians. It can also be said this way: 10 out of 100 students in this school are Asians.
To transform a fraction into a percent, the first thing to do is use the denominator to divide the numerator. Then multiply the quotient (result) by 100. Using a calculator is the quickest way to get the answer.
But, let's say you do not have a calculator. How do you convert a fraction into a percent?
Let us use one of the common fractions mentioned earlier: 1?8 = 12.5%
Here are the steps again so we can follow them:
- Divide the numerator by the denominator.
- Multiply the quotient or the result by 100.
- Add the percent symbol after the answer.
Step 1. Divide the numerator by the denominator.
Let's divide 1 by 8.
Since we cannot find any 8 in 1, we need to add a decimal point and a zero. This gives us 10, which has one 8 in it. So, we write 1 after the decimal point, on top of our division sign, then multiply it by 8, as shown below.
Next, we need to divide 2 by 8. So, we add another zero, bring that down next to 2, and we get 20. Since we know that there are two 8s in 20, we write 2 next to 1, above our division sign, and multiply 8 by 2, like so:
So, now we add one more zero, and bring it down next to 4, which gives us 40. We know that there are five 8s in 40, so we write 5 right next to 2, above our division sign. After that, we multiply 8 by 5.
We now have our answer to 1 divided by 8 in decimal form: 0.125.
Step 2. Multiply the quotient or the result by 100.
We now multiply 0.125 by 100:
0.125 x 100 = 12.5
As you can see above, when we multiplied our quotient with 100, we just moved the decimal point 2 places to the right. The number of places to move the decimal to corresponds to the number of zeroes after 1 in 100.
Step 3. Add the percent symbol after the answer.
12.5 -> 12.5%