We're going to solve 6640 multiplied by 3978
6640 × 3978 = 3978 × (6640)
+ 3978 × 0 that results in 0
+ 3978 × 40 which equals 159120
+ 3978 × 600 what gives us 2386800
+ 3978 × 6000 giving us 23868000

= 26413920
