Roman Numerals

72

Step 1: We need to find the value of LXXII. Step 2: L = 50, X = 10, X = 10, I = 1, I = 1. Step 3: Each letter is equal to or smaller than the one before it, so we add all values. Step 4: 50 + 10 + 10 + 1 + 1 = 72. The answer is 72. A common mistake is misreading L as 100 (L = 50, not 100 — that is C).

XLIX

Step 1: We need to write 49 in Roman numerals. Step 2: 49 = 40 + 9. Step 3: 40 = XL (50 - 10) and 9 = IX (10 - 1). Step 4: Combine: XL + IX = XLIX. IL is wrong because I can only be subtracted from V and X, not L. XXXXIX is wrong because X cannot be repeated 4 times. The correct answer is XLIX.

400

Step 1: We need to find the value of CD. Step 2: C = 100 and D = 500. Step 3: C is smaller than D and is placed to the left of D, so we subtract: D - C = 500 - 100 = 400. Step 4: The answer is 400. A common mistake is adding C and D to get 600, but since C comes before the larger D, we must subtract.

MMXXIV

Step 1: Break 2024 into parts: 2000 + 20 + 4. Step 2: 2000 = MM (M repeated twice). Step 3: 20 = XX (X repeated twice). Step 4: 4 = IV (5 - 1). Combine all parts: MM + XX + IV = MMXXIV. MMXXIIII is wrong because I can only be repeated 3 times. MMDXXIV would be 2524 (D = 500 is extra). The answer is MMXXIV.