$ modulo $28$ is $27$.
The value of X is 27.
The answer is: 27
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
Find the modular inverse of $27$, modulo $28$.

Express your answer as an integer from $0$ to X$, inclusive.
If we know the answer to the above question is 27, what is the value of unknown variable X?

### Answer:
