Statistics: Background You’ll Need 1

  • Write percents as ratios

Percents

How many cents are in one dollar? There are [latex]100[/latex] cents in a dollar. How many years are in a century? There are [latex]100[/latex] years in a century. Does this give you a clue about what the word “percent” means? It is really two words, “per cent,” and means per one hundred. A percent is a ratio whose denominator is [latex]100[/latex]. We use the percent symbol [latex]\text{%,}[/latex] to show percent.

percent

A percent is a ratio whose denominator is [latex]100[/latex].

How To: Convert a Percent to a ratio

  1. Write the Percent as a Fraction: Begin by writing the percent as a fraction with the percent number as the numerator and [latex]100[/latex] as the denominator.
  2. Remove the Percent Sign: When you write the percent as a fraction, omit the percent sign since you are now using the fraction format to represent the same value.
  3. Simplify the Fraction: Look for the greatest common divisor (GCD) of the numerator and the denominator and divide both by this number to simplify the fraction.
According to the Public Policy Institute of California [latex]\left(2010\right)\text{, }\text{44%}[/latex] of parents of public school children would like their youngest child to earn a graduate degree. Write this percent as a ratio.

In [latex]2007[/latex], according to a U.S. Department of Education report, [latex]21[/latex] out of every [latex]100[/latex] first-time freshmen college students at [latex]\text{4-year}[/latex] public institutions took at least one remedial course. Write this as a ratio and then as a percent.