To simplify the ratio $36:99$, we need to find the greatest common divisor (GCD) of 36 and 99, and divide both numbers by this GCD.

1. Find the GCD of 36 and 99:

   • The factors of 36 are: $1, 2, 3, 4, 6, 9, 12, 18, 36$
   • The factors of 99 are: $1, 3, 9, 11, 33, 99$
   • The greatest common divisor is $9$.

2. Divide both numbers by 9: $\frac{36}{9} = 4, \quad \frac{99}{9} = 11$

Thus, the simplified ratio is: $4:11$

Would you like further details on how to find the GCD or any other clarifications?

Here are 5 related questions:

1. What is the process for finding the GCD of two numbers?
2. Can you simplify the ratio $48:64$?
3. How do you express a ratio as a fraction?
4. What are some real-life applications of ratios?
5. How do you convert a ratio into a percentage?

Tip: Always divide a ratio by the GCD to ensure it is in its simplest form.