I believe it's 18. I put them in fractions, 3/20 = x/122 So I Divided 122 by 20 and I got 6.1 I multiple 3 by 6.1 and got 18.3 Rounding to the nearest whole number I got 18
To know the answer to this question you just have to do a rule of three, this is when you have a ratio of margin and the number you are trying to figure out with that margin.
In this case your ratio of margin would be 3 out of 20, and you want to discover how many out of 122, this would be expressed in the next way: