Alright, let's work through 8190 times 4890 step by step
8190 × 4890 = 4890 × (8190)
+ 4890 × 0 giving us 0
+ 4890 × 90 that is equal 440100
+ 4890 × 100 giving us 489000
+ 4890 × 8000 what gives us 39120000

= 40049100
