29 persons can repair a road in 16 days, working 5 hours a day. In how many days will 30 persons, working 6 hours a day, complete the work? Pick:
A) 12.88
B) 3.88
C) 13.88
D) 15
E) 18.8

Rationale: "let the required number of days be x more persons , less days ( indirect proportion ) more hours , less days ( indirect proportion ) hence we can write as ( persons ) 29 : 30 } : : x : 16 ( hours ) 5 : 6 29 * 5 * 16 = 30 * 6 * x x = 12.88 answer : a"
Answer: A