Alright, let's work through 4239 times 902 step by step
4239 × 902 = 902 × (4239)
+ 902 × 9 yielding 8118
+ 902 × 30 resulting in 27060
+ 902 × 200 yielding 180400
+ 902 × 4000 resulting in 3608000

= 3823578
