Alright, let's work through 1506 times 4188 step by step
1506 × 4188 = 4188 × (1506)
+ 4188 × 6 what gives us 25128
+ 4188 × 00 resulting in 0
+ 4188 × 500 giving us 2094000
+ 4188 × 1000 giving us 4188000

= 6307128
