Alright, let's work through 9920 times 4239 step by step
9920 × 4239 = 4239 × (9920)
+ 4239 × 0 that is equal 0
+ 4239 × 20 that results in 84780
+ 4239 × 900 resulting in 3815100
+ 4239 × 9000 that equals 38151000

= 42050880
