Work Out the Angle Between the Clock Hands at 3:15
Key Takeaway
Yesterday's Quiz 6 answer is U. Today's Quiz 7 asks for the smaller angle between the hour hand and minute hand at 3:15. Don't forget the hour hand creeps along too. Today's answer goes up tomorrow in Quiz 8.
What was yesterday's answer?
Quiz 6 asked for the letter after A, C, F, J, O. The answer is U.
| Letter | A | C | F | J | O | U |
|---|---|---|---|---|---|---|
| Position number | 1 | 3 | 6 | 10 | 15 | 21 |
| Difference from previous | - | 2 | 3 | 4 | 5 | 6 |
The differences grow by one each time, so after the 15th letter O comes the 15+6=21st letter, U.
What is today's puzzle?
An ordinary analog clock with two hands (hour and minute) shows 3:15.
- Question: How many degrees is the smaller angle between the hour hand and the minute hand?
- Condition: both hands keep moving at a steady speed without stopping
- Difficulty: ★★★☆☆
- Suggested time: 3 minutes
Where should you start?
If you feel like answering "0 degrees," look at the hour hand again. At exactly 3:00 the hour hand points at the 3, but over the next 15 minutes it moves a little toward the 4. First work out how many degrees each hand moves per minute.
| Hand | Time for one full turn (360 degrees) | Degrees moved per minute |
|---|---|---|
| Minute hand | 60 minutes | Calculate it yourself |
| Hour hand | 12 hours (720 minutes) | Calculate it yourself |
When can you check the answer?
The answer and explanation go up tomorrow (October 20) morning, at the very top of the Quiz 8 post. It will also lay out a calculation you can use for other times right away.
What skills do clock puzzles test?
Clock angle puzzles combine spatial sense, picturing the hands moving in your head, with simple calculation. Mensa Korea describes its online brain test as looking at overall cognitive ability, including pattern recognition and logical thinking (checked 2026-10-13). Mensa International's standard for joining is a top 2% score on an approved intelligence test, and this puzzle is for practice.
Frequently Asked Questions
What is the answer to Quiz 6?
U. The differences between alphabet position numbers grow by one each time (2, 3, 4, 5), so 6 is added to O (15th), giving the 21st letter, U.
When does the Quiz 7 answer come out?
It goes up with the explanation at the very top of the Quiz 8 post, published the next day.
Should I answer with the smaller angle or the larger one?
Answer with the smaller angle between the two hands, that is, the angle of 180 degrees or less.
Sources & Verification Date
- Mensa International membership requirements guide · Verified
- Mensa Korea online brain test introduction · Verified
All materials have been verified from official announcements and may have changed since verification.