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BrainTwister #59 Seven segments

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

By Katie Steckles

5 February 2025

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.

#59 Seven segments

Set by Katie Steckles

An alarm clock has four digits. In each of these digits, up to seven segments light up in order to display numbers.

When the time changes from 04:59 to 05:00, will the room get very slightly brighter or darker?

Using a 12-hour clock, which time lights up the most segments and which time uses the fewest?

For which minute in the day is there the biggest change in brightness when it changes to the following minute?

Solution next week

#58 Fulfilling fractions

Solution

The largest result possible is 16⅓, which can…

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