Alright, let's work through 9942 times 8657 step by step
9942 × 8657 = 8657 × (9942)
+ 8657 × 2 yielding 17314
+ 8657 × 40 that equals 346280
+ 8657 × 900 giving us 7791300
+ 8657 × 9000 that is equal 77913000

= 86067894
