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BrainTwister #5: Diagonal lines

Can you solve this week’s logic puzzle? Plus our quick quiz and the answer to last week’s problem

By New Scientist

31 January 2024

New Scientist. Science news and long reads from expert journalists, covering developments in science, technology, health and the environment on the website and the magazine.

#5 Diagonal lines

Set by Katie Steckles

A square has two diagonals (lines that run from one corner to a different corner, but not between two corners on the same edge).

How many diagonals does a pentagon have? What about a hexagon?

What kind of regular polygon has a number of diagonals that is three times the number of its corners?

Solution next week

#4 Addition subtraction

Solution

For the four-number case, we can do 12 + 34 = 43 + 2 + 1.

For the five-number case, while 12 + 34 + 5 = 5 + 43 + 2 + 1 will…

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