Alright, let's work through 2640 times 3916 step by step
2640 × 3916 = 3916 × (2640)
+ 3916 × 0 producing 0
+ 3916 × 40 yielding 156640
+ 3916 × 600 giving us 2349600
+ 3916 × 2000 which equals 7832000

= 10338240
