Alright, let's work through 6440 times 8542 step by step
6440 × 8542 = 8542 × (6440)
+ 8542 × 0 resulting in 0
+ 8542 × 40 that results in 341680
+ 8542 × 400 yielding 3416800
+ 8542 × 6000 giving us 51252000

= 55010480
