Percents and Decimal Numbers

Our Pre-Algebra tutorial software program contains over 60 topic areas. One of them is Percents and Decimal Numbers, and this page summarizes the main ideas of this topic. This page is intended for review, and is not a substitute for the interactive, self-paced tutorials of the MathTutor pre-algebra software program.

General Explanation

In this lesson we will study PERCENT. Percent means hundredths. The symbol for percent is "%".
Let's write the fraction 50/100 as a percent:
50/100 = 50 hundredths = 50%
Here is another example:
3 = 1/2 of 6
3 = 50/100 of 6
3 = 50% of 6
To write a percent as a decimal number, do the following:
  1. Divide the number by 100 by moving the decimal point two places to the left.
  2. Drop the percent sign.
Sample Problem

Write 65% as a decimal number.


  1. First, divide the number by 100 by moving the decimal point to the left two places:
    65 ÷ 100 = 0.65
  2. Drop the percent sign to get a final answer of 0.65.