Let's call the number you thought of n. Then what the two steps you took can be written as an equation:

Subtract n to get all of your variables to one side:

At this point, I recommend turning your mixed number into an improper fraction. It will make things easier later on:

Now divide both sides by 11 to get the value of n:
4*m*3/3*m*2*n*x*9*n*2/30*m*2*n*2 evaluates to 96/5n^3m^3mx and that is the final answer.
Your answer will be H 170