Lemma
MediumRatio & rate
#98 · Arithmetic · Ratio & rate

There and back again

You drive to a town at km/h and return along the same road at km/h. What is your average speed for the round trip, in km/h?

~4 minAnswer checked instantlyAverage speedHarmonic mean
Stuck? A gentle nudge
Something off?
Workspace
Your answer
Loading the math keyboard…

Type naturally — sqrt, pi, / and ^ become notation. Any equivalent form is accepted. Press Enter to check.