Alright, let's work through 1355 times 9521 step by step
1355 × 9521 = 9521 × (1355)
+ 9521 × 5 that equals 47605
+ 9521 × 50 that results in 476050
+ 9521 × 300 that equals 2856300
+ 9521 × 1000 that equals 9521000

= 12900955
