We're going to solve 8509 multiplied by 8400
8509 × 8400 = 8400 × (8509)
+ 8400 × 9 resulting in 75600
+ 8400 × 00 what gives us 0
+ 8400 × 500 yielding 4200000
+ 8400 × 8000 producing 67200000

= 71475600
