On a particular day, Sylvia worked 3 hours and 45 minutes, while Paul worked 4 hours and 35 minutes. 9 / 11 is the ratio of Sylvia's work time to Paul’s work time in minutes. Solution: Sylvia's time: 3 hours and 45 minutes = 3 hours + 45 / 60 hours = 3hours + 0.75 hours = 3.75 hours; Paul's work time: 4 hours and 35 minutes = 4 hours + 35/60 hours = 4 hours + 7/12 hours = (48+7)/12 = 55/12 hours 4.58 hours; 3.75 hours/(55/12) hours = 3.75*12 / 55 = 45/55 = 9/11.