2026 · Q26
N is a 3-digit number. The middle digit of N is equal to the sum of the other two digits and the sum of the digits is 10. How many such numbers (N) can be possible?
Elementary MathematicsNumber System
- A3
- B4
- C5
- D6
Explanation
Let the digits be a, b, c with b = a + c and a + b + c = 10. Substituting gives 2b = 10, so b = 5 and a + c = 5. With a ≥ 1 (hundreds digit), the pairs (a, c) are (1,4), (2,3), (3,2), (4,1), (5,0) — 5 possibilities, option C.