# When Do the Three Hands of an Analog Clock Overlap?

Initializing live version

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram Player or other Wolfram Language products.

There is an interesting puzzle based on old-fashioned analog clocks.

[more]

Question: How many times a day are the three hands of a clock exactly in line? What are the exact times? How can you calculate them?

[less]

Contributed by: Frederick Wu (October 2008)
Open content licensed under CC BY-NC-SA

## Details

Answer: This Demonstration solves this puzzle by finding the 12 times.

Snapshot 1: the first moment that the three hands overlap is at 0:0:0 or 12:00:00

Snapshot 2: the second moment is at 1:05:05

Snapshot 3: the last moment is at 11:59:59

Tip: The "static" option is for turning the three hands to any position you want.

## Permanent Citation

Frederick Wu

 Feedback (field required) Email (field required) Name Occupation Organization Note: Your message & contact information may be shared with the author of any specific Demonstration for which you give feedback. Send