Question

The sum of the natural numbers from 1 to n is 36. find the value of n. plzz give mi a brief anss.


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Answer 1

Answer:

8

Step-by-step explanation:

sum of first n natural numbers = n(n+1)/2

n(n+1)/2=36

when solving we get n=8

Answer 2

$\red{QUESTION}$

The sum of the natural numbers from 1 to n is 36. find the value of n

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$\blue{ANSWER}$

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Using S to represent the sum of the natural numbers from 1 to n, we have:

S = 1 + 2 + … + (n-1) + n [A]

We can express this in another way.

S = n + (n-1) + … + 2 + 1 [B]

Adding A + B:

2S = [1+n] + [2+(n-1)] + … + [(n-1)+2] + [n+1] = n(n+1)

As S = 36, 2S = 72

So, we need to solve the equation n(n+1) = 72.

There are two possible solutions to this equation:

n = 8

n = -9

We can safely ignore the second answer as -9 is not a natural number.

∆ n=8

THE VALUE OF N = 8

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