Lemma
MediumArithmetical puzzles
#21 · Puzzles · A sneaky average

There and back

You drive 60 miles at 30 mph, then the same 60 miles back at 60 mph. What is your average speed for the whole trip? (It is not 45.)

~7 minWritten answer · check your work with LemmaAverage speedTotal distance over total time
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