Problem: what least number must be added to 3000 to obtain a number exactly divisible by 19 ?
Rationale: "on dividing 3000 by 19 , we get 17 as remainder .  number to be added = ( 19 - 17 ) = 2 . answer a 2"
annotated_formula: subtract(multiply(add(multiply(const_4, const_10), const_2), 19), 3000)