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My round

A group of friends and I each had a half-pint of shandy (beer mixed with lemonade), but the proportion of lemonade to beer varied from glass to glass. Overall, I had a certain whole-number percentage of the lemonade used in the round of drinks, and a certain whole-number percentage of the beer. The percentage of beer was 5 more than that of the lemonade.

If I now told you the actual percentages it would be possible to work out how many of us there were in the group.

Knowing that, if instead I now told you how many…

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