Alright, let's work through 8109 times 9542 step by step
8109 × 9542 = 9542 × (8109)
+ 9542 × 9 what gives us 85878
+ 9542 × 00 which equals 0
+ 9542 × 100 which equals 954200
+ 9542 × 8000 resulting in 76336000

= 77376078
