Sixty is 30% of what number?
60 is 30% of what number?
When encountering these type of questions, first identify the total number. The number after "of" or "out of" is the total number. In this case, they don't give us a number for total.
After that, look at the format
This problem gives us a percentage which is 30% and since it doesn't give us a total, then all that's left is 60 as our number.
You also would want to double check your answers because it is very easy to put the wrong value in the equation.
60 is 30% of 200