Problem: half a number plus 7 is 11 . what is the number ?
Rationale: "let x be the number . always replace ` ` is ' ' with an equal sign ( 1 / 2 ) x + 7 = 11 ( 1 / 2 ) x = 11 - 7 ( 1 / 2 ) x = 4 x = 8 correct answer is a"
annotated_formula: multiply(subtract(11, 7), const_2)