Percents, Fractions and Decimals
Quatr.us answers questions

Percents

Pennies

Percent comes from the Latin words "per cent" which means "out of a hundred," like there are 100 cents in a dollar. So "ten per cent" means ten out of every hundred. A dime is ten percent of a dollar, and a dollar is ten percent of ten dollars.

If we say that 50% (fifty percent) of people are women, that means that fifty out of a hundred people are women, or half of the people. If we say that 100% of people have hearts, that means that all of them do.

To calculate a percentage for yourself, you need to understand how to multiply fractions and simplify equations. Suppose you have sixty-five seeds, and ten of them have gone moldy, and you need to know what percentage of the seeds went bad. First write your problem as a fraction: 10/65: ten out of sixty-five seeds went bad.

Now you need to know how much that would be out of a hundred, so set it up as an equation:

10/65 = x/100

To solve this equation and find out what x is, you'll need to find a common denominator for your two fractions. Just use 6500 (65x100). Remember to multiply the numerators by the same amount as the denominators! So you get:

solving above equation

Percentages can also be more than 100 percent. If you planted ten good seeds, and they grew into a hundred peas, you'd have 1000% of your original seeds back, or ten times as much. If you weigh 100 pounds, and your little brother weighs 50 pounds, you weigh 200% as much as he does, or twice as much.

More about Decimals
More about Fractions

Bibliography and further reading about numbers:

More about Percents
More about Fractions
Quatr.us home


Professor Carr

Karen Eva Carr, PhD.
Assoc. Professor Emerita, History
Portland State University

Professor Carr holds a B.A. with high honors from Cornell University in classics and archaeology, and her M.A. and PhD. from the University of Michigan in Classical Art and Archaeology. She has excavated in Scotland, Cyprus, Greece, Israel, and Tunisia, and she has been teaching history to university students for a very long time.

Professor Carr's PSU page

Help support Quatr.us!

Quatr.us (formerly "History for Kids") is entirely supported by your generous donations and by our sponsors. Most donors give about $10. Can you give $10 today to keep this site running? Or give $50 to sponsor a page?

Happy New Year! Welcome back! Get ready for Martin Luther King day with these articles about medieval Africa, slavery, the Civil War, emancipation, the civil rights movement, and Martin Luther King Jr. himself. More about King here...