Alright, let's work through 9940 times 669 step by step
9940 × 669 = 669 × (9940)
+ 669 × 0 resulting in 0
+ 669 × 40 that is equal 26760
+ 669 × 900 that is equal 602100
+ 669 × 9000 which equals 6021000

= 6649860
