The clock at Ravi's house loses 3 minutes daily and his office clock gains 4 minutes daily. They are set right at 3 p.m. What time will the slower clock indicate the next day, when the office clock shows 9 p.m?

The clocks are set at 3 p.m. The office clock shows 9 p.m. the next day, which is 30 hours later. In 30 hours, the office clock gains 4 minutes/24 hours * 30 hours = 5 minutes. The actual time is 9 p.m. - 5 minutes = 8:55 p.m. The slower clock loses 3 minutes/24 hours * 30 hours = 3.75 minutes. So it shows 8:55 p.m. - 3.75 minutes = 8:51.25 p.m.