2015 · Q7
What is the remainder obtained when 1421 × 1423 × 1425 is divided by 12 ?
Elementary MathematicsNumber System
- A1
- B2
- C3
- D4
Explanation
1421 ≡ 5, 1423 ≡ 7, 1425 ≡ 9 (mod 12). Their product ≡ 5·7·9 = 315 ≡ 315 − 312 = 3 (mod 12), so the remainder is 3 (option C).