Iron Man - His Math Is Always Right
When Stark takes apart the first rocket warhead while in capitivity, Yinsen asks him what it is he removed. Stark explains that it is 0.15 grams of Paladium & that he needs 1.6 grams. He then tells Yinsen to "get started on the other 11." If he needs 1.6 grams total, and he already has 0.15 grams, then he only needs another 1.45 grams. Since each rocket provides 0.15 grams, he only needs 10 more, not 11. Since Stark is supposed to be a super genius, even commenting a few moments later that his math is "always right" he should have known this easily.