Problems

Blog posts with problems to get your brain going! You get a new problem every fortnight and the solutions are published later.

If you want the problems delivered to your inbox be sure to subscribe to the Problems newsletter.

The next problem is scheduled for late June.

You may notice some problems are missing... I'm still migrating articles from my old blog.

Problem #062 – sliding coins

Can you align all of the coins on the right edge of the board?

Problem #061 – flower garden

Three mathematicians discuss a beautiful flower garden and the coloured flowers within.

Problem #060 – realtor commissions

Two realtors discuss who's netting the award for highest average commission, but it isn't clear who the winner is...

Problem #059 – marching pegs

How can you swap the coloured pegs if they can only march forward?

Problem #055 – horse racing

25 horses racing, and you have to find out the fastest ones!

Problem #053 – weighing the odd one out

Can you find the fake ball by weighing it?

Problem #048 – trick or treat

Can you help these kids trick or treat their entire neighbourhood in this Halloween special?

Problem #047 – surgery gloves

How can two doctors operate two patients with only two pairs of latex gloves?!

Problem #045 – 1, 2, 3

Figure out the number I'm thinking of with a single question!

Problem #044 – send more money

Can you solve this simple-looking arithmetic challenge?

Problem #043 – Rubik's cube scrambling

If I scramble a Rubik's cube for long enough, will it solve itself?

Can you solve this little minesweeper puzzle?

Problem #041 – canyon crossing

It's night time and 4 friends need to cross a fragile bridge, but they only have one torch. What's the order in which they should cross?

Problem #040 – the dozen puzzle

Three friends are given three different numbers that add up to a dozen. Can you figure out everyone's numbers?

Problem #039 – rope timer

You have two magical ropes that you can set on fire and you need to count 45 minutes. How do you do it?

Problem #034 – one question to happiness

Two doors, one gives you eternal happiness and the other eternal sadness. How can you pick the correct one?