Alright, let's work through 1243 times 1840 step by step
1243 × 1840 = 1840 × (1243)
+ 1840 × 3 yielding 5520
+ 1840 × 40 producing 73600
+ 1840 × 200 that is equal 368000
+ 1840 × 1000 that equals 1840000

= 2287120
