Alright, let's work through 3729 times 7900 step by step
3729 × 7900 = 7900 × (3729)
+ 7900 × 9 which equals 71100
+ 7900 × 20 that is equal 158000
+ 7900 × 700 producing 5530000
+ 7900 × 3000 what gives us 23700000

= 29459100
