Alright, let's work through 3985 times 5104 step by step
3985 × 5104 = 5104 × (3985)
+ 5104 × 5 that is equal 25520
+ 5104 × 80 giving us 408320
+ 5104 × 900 that results in 4593600
+ 5104 × 3000 producing 15312000

= 20339440
