Can you sum the parts within ten seconds?

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Discussion Overview

The discussion revolves around a mathematical puzzle involving a cyclist and a bee, specifically focusing on the total distance the bee flies while the cyclist travels from point A to point B. The problem is framed as a challenge to solve quickly, with references to both mathematical reasoning and anecdotal context related to famous mathematicians.

Discussion Character

  • Exploratory
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • Some participants recount the problem as a challenge posed to a mathematician, highlighting the anecdote of John Von Neumann's approach to summing the series involved.
  • One participant expresses confusion regarding the bee's velocity, questioning whether it matches the cyclist's speed at any point.
  • Another participant clarifies that the bee consistently flies at 25 mph, suggesting a distinction between speed and velocity.
  • Concerns are raised about the implications of the bee's behavior, including the nature of its acceleration and the mathematical assumptions involved.
  • A humorous remark is made about the bee's fitness level due to its constant back-and-forth flight.

Areas of Agreement / Disagreement

Participants exhibit uncertainty regarding the interpretation of the bee's velocity and the implications of its flight pattern. There is no consensus on the correct understanding of the problem or the assumptions involved.

Contextual Notes

Some participants note potential ambiguities in the problem statement, particularly regarding the definitions of speed and velocity, as well as the mathematical treatment of the bee's flight path.

Ian
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I asked this of my maths lecturer in uni. He took about ten seconds to mentally perform the calculation/integration. Can you beat his time?

Q.
A cyclist rides 100 miles from point A to point B at a constant velocity of 20mph. As he leaves point A, a bee on his handlebars flies ahead of him toward point B at a steady velocity of 25mph. When the bee arrives at point B it immediately returns to meet the cyclist somewhere in-between. The bee then flies at the same velocity in-between point B and the cyclist until the cyclist reaches point B.
What distance does the bee fly in total? (you have ten seconds)
 
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Ian said:
I asked this of my maths lecturer in uni. He took about ten seconds to mentally perform the calculation/integration. Can you beat his time?

Q.
A cyclist rides 100 miles from point A to point B at a constant velocity of 20mph. As he leaves point A, a bee on his handlebars flies ahead of him toward point B at a steady velocity of 25mph. When the bee arrives at point B it immediately returns to meet the cyclist somewhere in-between. The bee then flies at the same velocity in-between point B and the cyclist until the cyclist reaches point B.
What distance does the bee fly in total? (you have ten seconds)
When the cyclist reaches point B, 5 hours will have passed. In those 5 hours the bee will have traveled 125 miles.
There's an interesting anecdote that goes with this puzzle. It was asked of the Mathematician John Von Neumann who pondered for a few moments and answered it. The puzzler said "Oh, yo u know the trick." and Von Neumann replied "No, I summed the series.". I had tried to sum the series when I was in High School and didn't know how to do it. However, when I heard the anecdote, (and after I learned how to do it), I tried again to sum the series and found it rather easy. Of course, the trick answer is even easier.
 
120?
 
Ian said:
The bee then flies at the same velocity in-between point B and the cyclist until the cyclist reaches point B.

I'm not sure I understand what this means. The bee travels the same velocity as the cyclist until the cyclist reaches point B?

I agree with CylonMath's answer, but Jimmysnyder is usually very accurate in his problem-solving abilities, so I'm doubting my answer.
 
The bee flies all the time at 25 mph.
 
DyslexicHobo said:
I'm not sure I understand what this means. The bee travels the same velocity as the cyclist until the cyclist reaches point B?
You (and the OP) mean speed, not velocity. I took the OP to mean that the bee traveled at 25 mph at all times. The infinite acceleration at the turning points, the infinite number of turns at the end of the flight, and the 5 hours of flight at 25mph indicate to me that this bee is a better mathematician than physicist.
 
Last edited:
Just imagine the kind of shape this bee is in after all those windsprints
 

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