Alright, let's work through 5143 times 2003 step by step
5143 × 2003 = 2003 × (5143)
+ 2003 × 3 resulting in 6009
+ 2003 × 40 which equals 80120
+ 2003 × 100 that is equal 200300
+ 2003 × 5000 resulting in 10015000

= 10301429
