Alright, let's work through 6669 times 6875 step by step
6669 × 6875 = 6875 × (6669)
+ 6875 × 9 what gives us 61875
+ 6875 × 60 giving us 412500
+ 6875 × 600 that equals 4125000
+ 6875 × 6000 that results in 41250000

= 45849375
