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Can you figure it out? Are you a creative problem solver?

It can be advantageous to take an unconventional approach when faced with a problem. The puzzles presented today all require a bit of creative thinking, as the initial step towards solving them may not be the most apparent.

1. Three cloves on an orange

If three points are randomly chosen on a sphere, what is the likelihood that they all lie on the same hemisphere?

2. A big number

What is the final digit when you multiply all prime numbers below one million?

A prime number is a number that can only be divided by itself and 1, such as 2, 3, 5, 7, 11, 13, and so on.

3. The three threes

Is it possible to create the number 20 using three instances of the number three and any mathematical operations?

[i.e you need to find an expression that includes 3, 3 and 3, and no other digits, but may include any other mathematical symbol, such as +, -, x, ÷, (, ), √, ., etc. An example might be 3√3

Dividing by 3 would be incorrect as it does not result in 20.

4. Square are you?

Can you divide this shape into four parts that can be put back together to make a square?

© CRC Press. From Lateral Solutions to Mathematical Problems by Des MacHale

5. Roamin’ numerals

Make the equation valid by moving exactly two matchsticks

© CRC Press. From Lateral Solutions to Mathematical Problems by Des MacHale

I kindly ask that you refrain from sharing any spoilers. I will be available again at 5pm in the UK. Instead, let’s have a conversation about your preferred instances of lateral thinking.

UPDATE: Click here to access the solutions.

Today’s puzzles are taken from Des MacHale’s book, “Lateral Solutions to Mathematical Problems.” The book contains over 100 problems from various areas of mathematics that require creative thinking for their solutions.

MacHale, emeritus professor at University College, Cork, is well known to readers of this column as an encyclopedia of mathematical humour. Hs latest book replaces the the “haha” with the “aha!”

(Hopefully, with minimal frustration!)

Since 2015, I have been posting a puzzle every other Monday and I am constantly searching for new, challenging puzzles. If you have any suggestions, please send me an email.

Source: theguardian.com