Alright, let's work through 4012 times 3960 step by step
4012 × 3960 = 3960 × (4012)
+ 3960 × 2 yielding 7920
+ 3960 × 10 resulting in 39600
+ 3960 × 000 that equals 0
+ 3960 × 4000 producing 15840000

= 15887520
