# Ratios

A
**
ratio
**
is a comparison of two numbers. It can be written with a colon (
$1:5$
), or using the word "to" (
$1$
to
$5$
), or as a fraction:
$\frac{1}{5}$

**
Example:
**

Write the ratio of blue dots to red dots in the figure.

There are $6$ blue dots and $4$ red dots.

Write the ratio as a fraction.

$\frac{6}{4}$

Now reduce the fraction .

$\frac{3}{2}$

So the ratio of
**
blue dots to red dots
**
is
$3:2$
.

(Note that the ratio of
**
red dots to blue dots
**
is the
reciprocal
:
$\frac{2}{3}$
or
$2:3$
.)