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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

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#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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