Alright, let's work through 9920 times 1008 step by step
9920 × 1008 = 1008 × (9920)
+ 1008 × 0 what gives us 0
+ 1008 × 20 which equals 20160
+ 1008 × 900 giving us 907200
+ 1008 × 9000 which equals 9072000

= 9999360
