Simplify the expression:
15 × 15 × 15 + 3 × 15 × 12 × 12 - 3 × 15 × 15 × 12 - 12 × 12 × 12
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 27.
15 × 15 × 15 + 3 × 15 × 12 × 12 - 3 × 15 × 15 × 12 - 12 × 12 × 12
= 153 - 3 × 152 × 12 + 3 × 15 × 122 - 123
= (15 - 12)3
= 33
= 27