Problem: a batsman in his 9 th inning makes a score of 75 and their by increasing his average by 7 . what is his average after the 9 th inning ?
Rationale: 8 x + 75 = 9 ( x + 7 ) x = 12 + 7 = 19 answer : b
annotated_formula: add(subtract(75, multiply(7, 9)), 7)