Alright, let's work through 3681 times 402 step by step
3681 × 402 = 402 × (3681)
+ 402 × 1 what gives us 402
+ 402 × 80 which equals 32160
+ 402 × 600 giving us 241200
+ 402 × 3000 which equals 1206000

= 1479762
