We're going to solve 3985 multiplied by 3960
3985 × 3960 = 3960 × (3985)
+ 3960 × 5 what gives us 19800
+ 3960 × 80 that results in 316800
+ 3960 × 900 giving us 3564000
+ 3960 × 3000 which equals 11880000

= 15780600
