Reaching the place of meeting 20 minutes before 8.50 hr Sumit found himself thirty minutes earlier than the man who came 40 minutes late. What was the scheduled time of the meeting?

Sumit arrived at 8:30 (20 minutes before 8:50). He was 30 minutes earlier than the person who was 40 minutes late. If scheduled time = T, late person arrived at T + 40. Sumit arrived 30 minutes before that person, so Sumit arrived at T + 40 - 30 = T + 10. But Sumit arrived at 8:30, so T + 10 = 8:30, which means T = 8:20.