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Four Points
Puzzles

Four Points

By Stephen Meskin
This problem concerns the number of ways of putting four distinct points in a (Euclidean) plane. But first, let me put the problem in context.

Addressing Addiction
End Paper

Addressing Addiction

By Sam Gutterman
Wow—my iPhone just told me that I only spent 4 hours and 47 minutes per day on my phone last week. At least that was a decrease of 5 percent over the previous week!