Alright, let's work through 3970 times 3958 step by step
3970 × 3958 = 3958 × (3970)
+ 3958 × 0 that is equal 0
+ 3958 × 70 that is equal 277060
+ 3958 × 900 that is equal 3562200
+ 3958 × 3000 that results in 11874000

= 15713260
