Alright, let's work through 8115 times 728 step by step
8115 × 728 = 728 × (8115)
+ 728 × 5 that is equal 3640
+ 728 × 10 that is equal 7280
+ 728 × 100 that is equal 72800
+ 728 × 8000 yielding 5824000

= 5907720
