Alright, let's work through 1720 times 4775 step by step
1720 × 4775 = 4775 × (1720)
+ 4775 × 0 that equals 0
+ 4775 × 20 that is equal 95500
+ 4775 × 700 yielding 3342500
+ 4775 × 1000 which equals 4775000

= 8213000
