Alright, let's work through 2560 times 7615 step by step
2560 × 7615 = 7615 × (2560)
+ 7615 × 0 resulting in 0
+ 7615 × 60 resulting in 456900
+ 7615 × 500 what gives us 3807500
+ 7615 × 2000 what gives us 15230000

= 19494400
