1. We assume, that the number 122 is 100% – because it’s the output value of the task. 
2. We assume, that x is the value we are looking for. 
3. If 100% equals 122, so we can write it down as 100%=122. 
4. We know, that x% equals 11 of the output value, so we can write it down as x%=11. 
5. Now we have two simple equations:
1) 100%=122
2) x%=11
where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that:
100%/x%=122/11
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 11 is what percent of 122

100%/x%=122/11
(100/x)*x=(122/11)*x       – we multiply both sides of the equation by x
100=11.0909090909*x       – we divide both sides of the equation by (11.0909090909) to get x
100/11.0909090909=x 
9.01639344262=x 
x=9.01639344262

now we have: 
11 is 9.01639344262% of 122