Riddle:
A professional fisherman caught 30 fish during a 5-day tournament. Each day, he caught three more fish than the day before. How many fish did the fisherman catch on the first day?
Answer: He didn't catch any fish the first day, but he caught 3 on the second day, 6 on the third day, 9 on the fourth day and 12 on the fifth day.
Riddle:
Two hours ago it was as long after one o'clock in the afternoon as it was before one o'clock in the morning. What time is it now?
Answer: It would be 9:00 pm. There are 12 hours between 1:00 pm and 1:00 am and half of that is six hours. Half-way between would be 7 o'clock. Two hours later it would be 9:00 o'clock.