Can you sum the parts within ten seconds?

AI Thread Summary
The discussion centers around a mathematical puzzle involving a cyclist and a bee, where the cyclist travels 100 miles at 20 mph and the bee flies ahead at 25 mph. The key question is to determine the total distance the bee flies before the cyclist reaches point B. The anecdote about mathematician John Von Neumann highlights his method of summing the series to arrive at the solution, contrasting with simpler approaches. Participants express confusion over the terminology used, particularly the distinction between speed and velocity, clarifying that the bee consistently flies at 25 mph. The conversation also touches on the complexities of the bee's flight path, emphasizing the mathematical intricacies involved in solving the problem. Overall, the thread showcases both the challenge of the puzzle and the varying interpretations of the bee's motion.
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.
 
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Just imagine the kind of shape this bee is in after all those windsprints
 
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