Alright, let's work through 4777 times 21 step by step
4777 × 21 = 21 × (4777)
+ 21 × 7 what gives us 147
+ 21 × 70 yielding 1470
+ 21 × 700 that results in 14700
+ 21 × 4000 that results in 84000

= 100317
