Alright, let's work through 3887 times 200 step by step
3887 × 200 = 200 × (3887)
+ 200 × 7 giving us 1400
+ 200 × 80 resulting in 16000
+ 200 × 800 giving us 160000
+ 200 × 3000 yielding 600000

= 777400
