The sum of the digits of a two-digit number is 15 and the difference between the digits is 3. What is the two-digit number?

• A. 78
• B. 69
• C. 96
• D. Cannot be determined

Answer: (D)

Let the ten's digit be x and unit's digit by yThen, x + y = 15 and x - y = 3 or y - x = 3Solving x + y = 15 and x - y = 3, we get: x = 9, y = 6Solving x + y = 15 and y - x = 3, we get: x = 6, y = 9So, the number is either 96 or 69.Hence, the number cannot be determined.