Problem: if 12 men or 20 women can do a piece of work in 54 days , then in how many days can 9 men and 12 women together do the work ?
Rationale: "e 40 days given that 12 m = 20 w = > 3 m = 5 w 9 men + 12 women = 15 women + 12 women = 27 women 20 women can do the work in 54 days . so , 27 women can do it in ( 20 * 54 ) / 27 = 40 days ."
annotated_formula: inverse(add(divide(9, multiply(12, 54)), divide(12, multiply(20, 54))))