Alright, let's work through 5200 times 731 step by step
5200 × 731 = 731 × (5200)
+ 731 × 0 yielding 0
+ 731 × 00 giving us 0
+ 731 × 200 what gives us 146200
+ 731 × 5000 producing 3655000

= 3801200
