Problem: if a card is drawn from a well shuffled pack of cards , the probability of drawing a spade or a king is - .
Rationale: "explanation : p ( s ᴜ k ) = p ( s ) + p ( k ) - p ( s ∩ k ) , where s denotes spade and k denotes king . p ( s ᴜ k ) = 13 / 52 + 4 / 52 - 1 / 52 = 4 / 13 answer : b"
annotated_formula: add(divide(const_3, const_52), divide(divide(const_52, const_4), const_52))