Arithmetic and Geometric Series (tortoise and the hare)

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Homework Help Overview

The discussion revolves around the concepts of arithmetic and geometric series, particularly in the context of a problem involving a tortoise and a hare. The original poster presents equations related to the sums of these series and attempts to analyze the completion times of both participants in a race.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to apply the formulas for the sums of arithmetic and geometric series to determine the race outcomes. They express confusion about the hare's completion time, questioning whether it can ever finish the race based on their calculations.

Discussion Status

Participants are actively engaging with the problem, with some suggesting that the hare will finish the race but takes an infinite amount of time. There is a discussion about the implications of this conclusion, with questions raised about the nature of infinite time and potential contradictions in the reasoning.

Contextual Notes

There is a mention of the original poster's calculations and assumptions regarding the race dynamics, particularly the interpretation of the hare's completion time in relation to the geometric series. The discussion reflects on the nature of convergence in series and the implications for the problem at hand.

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Homework Statement


The question is attachedk


Homework Equations


Sn = n/2[2a+(n-1)d]
Sn = (a x (1-r^n))/1-r


The Attempt at a Solution


I already found the general formulas:
Tortoise:
Sn = n/2(40)
Hare:
Sn = (1000 x [1-0.5^n])/0.5

And I know that there tortoise will finish the race in 100 minutes. But I don't think the hare ever finishes the race? This is the work I did so far trying to solve for the hare:
2000 = (1000(1-0.5^n))/0.5
1000 = 1000(1-0.5^n)
1 = 1-0.5^n
2 = 0.5^n
But 0.5 the the power of anything can never equal 2?

Thank you!
 
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Correction* 0 = 0.5^n
Is that the solution? The hare can never finish the race because no matter what value n is, it can never equal 0?
 
Correction: it will eventually finish, but takes an infinite amount of time
 
eddybob123 said:
Correction: it will eventually finish, but takes an infinite amount of time
Isn't that a contradiction of terms?
 

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