Percent and Interest
Introduction to percent
Whole, half, quarter, fifth and tenth
Fractions, decimal numbers and percent
Part, portion and percentage
![Introduction to percent](https://static.studi.se/lessons/thumbs_small/MAH169.png)
Introduction to percent
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What is as a percentage?
How much do two sevenths of this sack of wheat cost? Wait, how much do three fifths cost? Or no, four ninths? Comparing fractions with different denominators is hard. This is why Romans started to describe quantities in hundredths.
Even when smaller denominators could do. This is what it might have sounded like. Imagine that you divide the sack of wheat into a hundred parts. I want to buy 20 of those hundred parts. In Latin, the language of the Romans, they used the words per centum by hundred.
Today, we say percent and it means one hundredth. The percent has its own symbol which looks like this, a slanted line with two small circles. A percent means one hundredth. When you calculate percentages, 100 means the whole. It can be a full sack of wheat or a tray of cakes.
First, take the whole and divide it into 100 equal pieces, then count how many pieces you have. This is the percentage you have. If you have 50 out of 100 pieces, you have 50% or a half. If you have 25 out of 100 pieces, you have 25% or a quarter. If you have 99 out of 100 pieces, you have 99% or almost everything.
Now can't you share some percentage, Scrooge? There's a simple formula for calculating the percentage of something, the part divided by the whole. Take the part, for example, three cakes that you've just eaten. The part divided by the whole. The whole is 30 cakes that were on the tray in the beginning.
The part divided by the whole- 3 divided by 30. That's one tenth or 0,1. A percent means one hundredth. How many hundredths are there here? 0,1 is ten hundredths, 10%.
You ate 10% of the cakes. Percent. This is a way to describe a share. The word percent means one hundredth. To calculate the percentage, take the part divided by the whole.