# In this Section:

In this section, we revisit the concept of a proportion. A proportion exists when two fractions/ratios/rates are equal in value.
We can test for proportionality using the equality test for fractions. Essentially this test tells us to multiply the denominator of one fraction by the
numerator of the other. If the two products are equal, then we have a proportion. When the two products are not equal, then we do not have a proportion.
We will also learn how to setup and solve a proportion equation. To do this, we utilize the same reasoning from the equality test for fractions and simply cross
multiply to setup an equation. We can then use our four step method to solve the equation, report, and check the answer.