**Math is hard...**

There are different ways to get the bars equal to seconds-- 2/4 time signature & 120 BPM or 4/4 time signature & 60 BPM. But then I heard you can also get it from a 1/4 time signature & 60 BPM. Is this correct? It just confuses me how the same BPM with a 1/4 vs 4/4 time signature would equal the same result of the seconds at a whole number.