How to Use Cross-Multiplication to Compare Two Ratios

1. Find the Ratios: First, look at two ratios. For example, let's use $a:b$ and $c:d$. Sometimes it can be hard to read these correctly.

2. Do the Cross-Multiplication: To set this up, multiply the numbers across the ratios. So, you will calculate $a \times d$ and $b \times c$. Make sure you keep the order correct. If not, your comparison might be wrong.

3. Compare the Results: Now it's time to see what you got! If $a \times d$ is greater than $b \times c$, then $a:b$ is also greater than $c:d$. If it’s the other way around, then $c:d$ is greater.

This process is simple, but it can feel a bit tricky when you’re working through the numbers. The more you practice, the easier it gets!