rebecca ' s annual income is $ 15 , and jimmy ' s annual income is $ 18 . by how much must rebecca ' s annual income increase so that it constitutes 50 % of rebecca and jimmy ' s combined income ?
"total rebecca = x + 15 ; total = x + 20 + 18 x + 15 / x + 33 = 50 / 100 therefore x = 3 d"
negate(divide(subtract(multiply(add(15, 18), divide(50, const_100)), 15), subtract(const_1, divide(50, const_100))))