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BrainTwister #1: Digital sevens

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

By New Scientist

3 January 2024

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#1 Digital sevens

Set by Katie Steckles

Welcome to our new puzzle column!

Our devious BrainTwister enigmas will start with a first step, then add a twist (or two) to get you thinking about the problem differently.

61, 14234, 25, 1111111 and 95 are all numbers whose digits add to a multiple of 7.

What is the next number after 95 whose digits add to a multiple of 7?

Can you find a pair of consecutive numbers whose digits both add to multiples of 7?

What about a pair of numbers under 100 whose digits both add to multiples of…

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