What is the sum of integers from 1 to n with r = 1 if n = 20?

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Homework Help Overview

The discussion revolves around the sum of integers from 1 to n, specifically when n is set to 20, and the role of a variable r in the context of this summation. Participants are exploring the relationship between these variables and the mathematical expressions involved.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants attempt to clarify the expression involving r and its significance in the summation. Some suggest interpreting the problem through number theory, while others question the meaning of r and its connection to the sum of integers.

Discussion Status

There is an ongoing exploration of the problem with various interpretations being discussed. Some participants provide alternative formulations and equations, while others express uncertainty about the original intent of the problem. Guidance has been offered regarding the standard formula for the sum of integers, but no consensus has been reached on the role of r.

Contextual Notes

Participants note a lack of clarity regarding the variable r and its implications within the problem. There is also mention of viewing the problem as involving diophantine equations, indicating a potential complexity in the interpretation.

tharindhudg
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sum of 1 n = 20/ r = 1
r(r+1)
 
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tharindhudg said:
sum of 1 n = 20/ r = 1
r(r+1)

It would help if you could clarify your expression.
 
tharindhudg said:
sum of 1 n = 20/ r = 1
r(r+1)

If construed as a number theory problem, the best that I could come up with

sum of 1 to n = r(r+1) sum of 1 to 3 = 2*3 etc.
sum of 1 to n = 20/r sum of 1 to 4 = 20/2
So r = 2
 
Last edited:
If I understand you correctly, you are summing the integers from 1 to n.
This sum is n(n+1)/2. I have no idea what you mean by r.
 
This topic made me laugh for some reason.
 
mathman said:
If I understand you correctly, you are summing the integers from 1 to n.
This sum is n(n+1)/2. I have no idea what you mean by r.

I viewed it as two diophantine equations in two variables

n(n+2)/2 = r(r+1) and m(m+1)/2 = 20/r for which the only solution is n = 3, m =4, r = 2

I did not use the formula n(n+1)/2 since I knew the values of n(3) and n(4) already.

No certainty that I understood the problem correctly though I don't see how there could be a different problem intended.
 

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