We are given that the base-6 representation of $X$ is 2215.
To find the value of $X$, we need to convert this base-6 number to base-10.
In base-6, each digit represents a power of 6.
The rightmost digit represents $6^0$, the next digit represents $6^1$, the next digit represents $6^2$, and so on.
So, we can convert 2215 from base-6 to base-10 using the following calculation:
$2 * 6^3 + 2 * 6^2 + 1 * 6^1 + 5 * 6^0$
Simplifying this calculation, we get:
$2 * 216 + 2 * 36 + 1 * 6 + 5 * 1$
$432 + 72 + 6 + 5$
$515$
Therefore, the value of $X$ is 515.
The answer is: 515
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
What is the base-10 integer X when expressed in base 6?
If we know the answer to the above question is 2215_6, what is the value of unknown variable X?

### Answer:
