We're going to solve 1821 multiplied by 2142
1821 × 2142 = 2142 × (1821)
+ 2142 × 1 resulting in 2142
+ 2142 × 20 resulting in 42840
+ 2142 × 800 that is equal 1713600
+ 2142 × 1000 yielding 2142000

= 3900582
