BrainTwister #26: Up and down

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

26 June 2024

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#26 Up and down

Set by Peter Rowlett

Which is bigger, 30 × 30 or 29 × 31?

If we choose a number other than 30 and compare its product with itself to the product of the numbers one above and one below it, which is bigger? Does this always work the same way?

If you choose any two numbers that are above and below 30 by the same amount, what is the difference between their product and 30 × 30?

Solution next week

#25 Triangles in circles

Solution

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.

From seven points you can make four triangles, and from 12 points, 12 triangles.…

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BrainTwister #26: Up and down

Shutterstock/ktsdesign

#26 Up and down

#25 Triangles in circles

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