What number do the Roman numerals XLIX represent?

Answer 1

When a smaller numeral comes before a larger numeral it is subtracted.
L = 50
X = 10
I = 1
→ XLIX = (-10 + 50) + ( -1 + 10) = 40 + 9 = 49

Answer 2

L represents 50 and X represents 10. Since the X comes before the L you subtract it to give 49.