We want to find the value of $X$ in the given situation.
The number of different dress designs can be found by multiplying the number of available fabric colors ($X$) by the number of available patterns (4):
Number of dress designs = $X$ * 4
Given that the number of dress designs is 12, we can write:
$X$ * 4 = 12
To find the value of $X$, we can divide both sides of the equation by 4:
$X$ = 12 / 4
$X$ = 3
The value of $X$ is 3.
The answer is: 3
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
A designer has X fabric colors he may use for a dress: red, green, and blue. Four different patterns are available for the dress. If each dress design requires exactly one color and one pattern, how many different dress designs are possible?
If we know the answer to the above question is 12, what is the value of unknown variable X?

### Answer:
