Question

33 is 33% of what number?

Answer 1

33 is 33% of 100.
When you see that a number is the same as the percentage that is given. That usually means that it is out of 100. Therefore taking 33% out of 100 is simply 33.

Answer 2

here's a hack
1% means 1/100

if 33=33/100 and you want to find 100/100 then since the numbers correspond, you just assume that 100% is 100