What does y mean in roman numerals?

Answer 1

150, though it is rarely, if ever, used because it does not fit the decimal numbering system that prevails nowadays.

Answer 2

In Roman numerals, "Y" does not represent any specific value. The Roman numeral system is based on combinations of the letters I, V, X, L, C, D, and M. These letters represent the values 1, 5, 10, 50, 100, 500, and 1000, respectively.