How Many Days?

How many days are there between February 25th 2000 and March 11th?

Planet Plex Time

On Planet Plex, there are only 6 hours in the day. Can you answer these questions about how Arog the Alien spends his day?

On What Day Did it Happen?

Read this article to find out the mathematical method for working out what day of the week each particular date fell on back as far as 1700.

Stop the Clock

Stage: 1 Challenge Level:

A number of pupils from Mortimer School in England sent in their solutions.
Here are their comments:

Alice and Oliver:

When your partner is doing 1/2  an hour you should do a 1 hour.

Aaron and Mustafa:
Get the clock on to half past ten and then try and make him use half an hour and you use 1 hour so it goes on to 12 o'clock.

What would happen if your partner didn't use half an hour?  Could you still win?

Harry and Gabe:
I pressed 1 hour when it was 11

Luke and Eve:
We think that you have to press 5 hours and 2 half hours for player 1 to win the game and 4 hours and 3 half hours for player 2 to win the game.

Dylan and Jacob:
We wrote that we did 1 hours and half an hour.

Thank you very much for these contributions.  The difficulty is to find a way of winning that ALWAYS works.

Rhys from St. Michael's on the Mount in Bristol, England, sent in this email:

With this strategy if you go second you are guaranteed to win.
The aim is to get to 7.30, then 9.00, then 10.30 - after that you have won.
If player one goes to 6.30 you would go 1 hour to 7.30.
If player 1 goes to 7.00 on their opening move you would then go half an hour to 7.30.

That is a fantastic strategy, Rhys.  I wonder if anyone can explain why it works?