Alright, let's work through 3504 times 7878 step by step
3504 × 7878 = 7878 × (3504)
+ 7878 × 4 that equals 31512
+ 7878 × 00 what gives us 0
+ 7878 × 500 that equals 3939000
+ 7878 × 3000 producing 23634000

= 27604512
