That is clever! The phrase "add the numbers" means both SUPPLY the missing numbers, and also add the numbers named by each line.

However, I think you need to have
SIX DIVIDE BY three
because your answer gives 5424, not 5423.

--Stuart Anderson

>
>NINE MULTIPLY BY six hundred
>
>SIX DIVIDE BY two
>
>TWO ADD NINETEEN
>
>5423