Spinning in Circles

We humans are traveling around in circles without even knowing it. We travel a circle around the axis of the earth once a day, and an almost-circle around the sun once a year. Considering each trip independently, how fast do we travel in each circle? (Assume we’re on the equator.) Here are some helpful data:

  • The diameter of the Earth is 12,756 km at the equator;
  • The distance from the Earth to the sun is 149,600,000 km;
  • There are 365.26 days in a year.
  • Give each answer in kilometers per hour.

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    Gertrude Goldfish

    Two young men in tuxedos are walking down the street at about 10 pm. One of them is carrying a round goldfish bowl filled with water. There is a goldfish, named Gertrude, in the bowl. As they pass a round pool in the park, the goldfish gets very excited and jumps out of the bowl into the pool, right at the edge. She starts swimming due north. She hits the wall after she has swum exactly 30 feet. She heads east, and, after going 40 feet, she hits the wall again. Once she regains consciousness after this second collision, she calculates the diameter of the pool. What is it? And what is the story about the two guys in their tuxes?

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